The Structural Integrity of the Model Lipid Membrane during Induced Lipid Peroxidation: The Role of Flavonols in the Inhibition of Lipid Peroxidation

Fermentation of Lactobacillus fermentum NB02 with feruloyl esterase production increases the phenolic compounds content and antioxidant properties of oat bran

In this study, strains producing feruloyl esterase were screened by Oxford Cup clear zones method and by evaluating the ability to decompose hydroxycinnamoyl esters. The strain was identified by 16S rDNA molecular biology. The contents of dietary fiber, reducing sugar, water-extractable arabinoxylans, phytic acid, total phenolics, total flavonoid, phenolic compounds composition, microstructure and antioxidant activity in bran before and after fermentation were studied. Eight strains producing feruloyl esterase were screened, among which strain P1 had the strongest ability to decompose hydroxycinnamoyl esters. The strain was identified and named L. fermentum NB02. Compared with unfermented bran, fermented bran exhibited higher contents of soluble dietary fiber, reducing sugar, water-extractable arabinoxylans, total phenolics, total flavonoid, and lower insoluble dietary fiber and phytic acid content. The dense surface structure of bran was destroyed, forming a porous structure. The release of phenolic compounds increased significantly. L. fermentum NB02 fermentation improved the antioxidant capacity of bran.

Dynamic interplay of metal and metal oxide nanoparticles with plants: Influencing factors, action mechanisms, and assessment of stimulatory and inhibitory effects

Nanoparticles (NPs) of metals and metal oxides have received increasing attention regarding their characteristic behavior in plant systems. The fate and transport of metal NPs and metal oxide NPs in plants is of emerging concern for researchers because they ultimately become part of the food chain. The widespread use of metal-based NPs (MBNPs) in plants has revealed their beneficial and harmful effects. This review addresses the main factors affecting the uptake, translocation, absorption, bioavailability, toxicity, and accumulation of MBNPs in different plant species. It appraises the mechanism of nanoparticle-plant interaction in detail and provides understanding of the estimation strategies for the associated pros and cons with this interplay. Critical parameters of NPs include, but are not limited to, particle size and shape, surface chemistry, surface charge, concentration, solubility, and exposure route. On exposure to MBNPs, the molecular, physiological, and biochemical reactions of plants have been assessed. We have filled knowledge gaps and answered research questions regarding the positive and negative effects of metal and metal oxide NPs on seed germination, callus induction, growth and yield of plant, nutritional content, antioxidants, and enzymes. Besides, the phytotoxicity, cytotoxicity, genotoxicity, and detoxification studies of MBNPs in plants have been outlined. Furthermore, the recent developments and future perspectives of the two-way traffic of interplay of MBNPs and plants have been provided in this comprehensive review.

Ginkgo biloba extract protects against tartrazine-induced testicular toxicity in rats: involvement of antioxidant, anti-inflammatory, and anti-apoptotic mechanisms

The use of additives, especially colorants, in food and pharmaceutical industry is increasing dramatically. Currently, additives are classified as contaminants of emerging concern (CECs). Concerns have been raised about the potential hazards of food additives to reproductive organs and fertility. The present study investigates the reproductive toxicity of tartrazine (TRZ), a synthetic colorant, in male rats and aims to explore the curative effect of Ginkgo biloba extract (EGb) against TRZ-induced testicular toxicity. Twenty-four rats were divided into four groups: the control (0.5 ml distilled water), the EGb group (100 mg/kg EGb alone), the TRZ group (7.5 mg/kg TRZ alone), and the TRZ-EGb group (7.5 mg/kg TRZ plus 100 mg/kg EGb). The doses were administered orally in distilled water once daily for 28 days. Toxicity studies of TRZ investigated testicular redox state, serum gonadotropins, and testosterone levels, testicular 17 ß-hydroxysteroid dehydrogenase activity, sperm count and quality, levels of inflammatory cytokines, and caspase-3 expression as an apoptotic marker. Also, histopathological alterations of the testes were examined. TRZ significantly affected the testicular redox status as indicated by the increase in malondialdehyde and the decrease in reduced glutathione, superoxide dismutase, and catalase. It also disrupted serum gonadotropins (follicle stimulating hormone and luteinizing hormone) and testosterone levels and the activity of testicular 17ß-hydroxysteroid dehydrogenase. Additionally, TRZ adversely affected sperm count, motility, viability, and abnormality. Levels of tumor necrosis factor-α, interleukin-1β, interleukin-6, and expression of caspase-3 were increased in the testes. Histopathological examination of the testes supported the alterations mentioned above. Administration of EGb significantly ameliorated TRZ-induced testicular toxicity in rats. In conclusion, EGb protected against TRZ-induced testicular toxicity through antioxidant, anti-inflammatory, and anti-apoptotic mechanisms.

Research Progress of Antioxidants in Oxidative Stress Therapy after Spinal Cord Injury

Spinal cord injury (SCI) is a serious problem in the central nervous system resulting in high disability and mortality with complex pathophysiological mechanisms. Oxidative stress is one of the main secondary reactions of SCI, and its main pathophysiological marker is the production of excess reactive oxygen species. The overproduction of reactive oxygen species and insufficient antioxidant capacity lead to the occurrence of oxidative stress and neuroinflammation, and the dysregulation of oxidative stress and neuroinflammation leads to further aggravation of damage. Oxidative stress can initiate a variety of inflammatory and apoptotic pathways, and targeted antioxidant therapy can greatly reduce oxidative stress and reduce neuroinflammation, which has a certain positive effect on rehabilitation and prognosis in SCI. This article reviewed the research on different types of antioxidants and related treatments in SCI, focusing on the mechanisms of oxidative stress.

Liposomal Encapsulation of Citicoline for Ocular Drug Delivery

Glaucoma represents a group of neurodegenerative diseases characterized by optic nerve damage and the slowly progressive death of retinal ganglion cells. Glaucoma is considered the second leading cause of irreversible blindness worldwide. Pharmaceutical treatment of glaucoma is critical because of the properties of the ocular barrier that limit the penetration of drugs, resulting in lower systemic bioavailability. This behavior causes the need of frequent drug administration, which leads to deposition of concentrated solutions on the eye, causing toxic effects and cellular damage to the eye. To overcome these drawbacks, novel drug-delivery systems, such as liposomes, can play an important role in improving the therapeutic efficacy of antiglaucomatous drugs. In this work, liposomes were synthesized to improve various aspects, such as ocular barrier penetration, bioavailability, sustained release of the drug, targeting of the tissue, and reduction in intraocular pressure. Citicoline (CDP-choline; cytidine 5'-diphosphocholine) is an important intermediate in the biosynthesis of cell membrane phospholipids, with neuroprotective and neuroenhancement properties, and it was used in the treatment on retinal function and neural conduction in the visual pathways of glaucoma patients. In this study, citicoline was loaded into the 1,2-dioleoyl-sn-glycerol-3-phosphocholine and cholesterol liposomal carrier to enhance its therapeutic effect. The citicoline encapsulation efficiency, drug release, and size analysis of the different liposome systems were investigated using dynamic light scattering, nuclear magnetic resonance, infrared spectroscopy, and ToF-SIMS experiments.

Kinetics of Flavonoid Degradation and Controlled Release from Functionalized Magnetic Nanoparticles

Flavonoids are naturally occurring antioxidants that have been shown to protect cell membranes from oxidative stress and have a potential use in photodynamic cancer treatment. However, they degrade at physiological pH values, which is often neglected in drug release studies. Kinetic study of flavonoid oxidation can help to understand the mechanism of degradation and to correctly analyze flavonoid release data. Additionally, the incorporation of flavonoids into magnetic nanocarriers can be utilized to mitigate degradation and overcome their low solubility, while the release can be controlled using magnetic fields (MFs). An approach that combines alternating least squares (ALS) and multilinear regression to consider flavonoid autoxidation in release studies is presented. This approach can be used in general cases to account for the degradation of unstable drugs released from nanoparticles. The oxidation of quercetin, myricetin (MCE), and myricitrin (MCI) was studied in PBS buffer (pH = 7.4) using UV-vis spectrophotometry. ALS was used to determine the kinetic profiles and characteristic spectra, which were used to analyze UV-vis data of release from functionalized magnetic nanoparticles (MNPs). MNPs were selected for their unique magnetic properties, which can be exploited for both targeted drug delivery and control over the drug release. MNPs were prepared and characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, superconducting quantum interference device magnetometer, and electrophoretic mobility measurements. Autoxidation of all three flavonoids follows a two-step first-order kinetic model. MCE showed the fastest degradation, while the oxidation of MCI was the slowest. The flavonoids were successfully loaded into the prepared MNPs, and the drug release was described by the first-order and Korsmeyer-Peppas models. External MFs were utilized to control the release mechanism and the cumulative mass of the flavonoids released.

Puncturing lipid membranes: onset of pore formation and the role of hydrogen bonding in the presence of flavonoids

Products of lipid peroxidation induce detrimental structural changes in cell membranes, such as the formation of water pores, which occur in the presence of lipids with partially oxidized chains. However, the influence of another class of products, dicarboxylic acids, is still unclear. These products have greater mobility in the lipid bilayer, which enables their aggregation and the formation of favorable sites for the appearance of pores. Therefore, dodecanedioic acid (DDA) was selected as a model product. Additionally, the influence of several structurally different flavonoids on DDA aggregation via formation of hydrogen bonds with carboxyl groups was investigated. The molecular dynamics of DDA in DOPC lipid bilayer revealed the formation of aggregates extending over the hydrophobic region of the bilayer and increasing its polarity. Consequently, water penetration and the appearance of water wires was observed, representing a new step in the mechanism of pore formation. Furthermore, DDA molecules were found to interact with lipid polar groups, causing them to be buried in the bilayer. The addition of flavonoids to the system disrupted aggregate formation, resulting in the displacement of DDA molecules from the center of the bilayer. The placement of DDA and flavonoids in the lipid bilayer was confirmed by small-angle X-ray scattering. Atomic force microscopy and electron paramagnetic resonance were used to characterize the structural properties. The presence of DDA increased bilayer roughness and decreased the ordering of lipid chains, confirming its detrimental effects on the membrane surface, while flavonoids were found to reduce or reverse these changes.

Permeability of antioxidants through a lipid bilayer model with coarse-grained simulations

Oxidative stress caused by pollution and lifestyle changes causes an excess of free radicals that react chemically with cell constituents leading to irreversible damage. There are molecules known as antioxidants that reduce the levels of free radicals. Some pigments of fruits and vegetables known as anthocyanins have antioxidant properties. Their interaction with the cell membrane becomes a crucial step in studying these substances. In this research, molecular dynamics simulations, particularly, coarse-grained molecular dynamics (CGMD) were used. This technique aims to replace functional groups with corresponding beads that represent their level of polarity and affinities to other chemical groups. Also, umbrella sampling was carried out to obtain free energy profiles that describe well the orientation and location of antioxidants in a membrane considering Trolox, Cyanidin, Gallic Acid, and Resveratrol molecules to study the structural effects they cause on it. It was concluded in this study that an antioxidant when crossing the membrane does not cause either damage to the structural properties or the loss of packing and stratification of phospholipids. it was also observed that the most reactive part of the molecules could easily approach area A prone to lipid oxidation, which can describe the antioxidant capacity of these molecules.Communicated by Ramaswamy H. Sarma.

Oxidized Soybean Oil Evoked Hepatic Fatty Acid Metabolism Disturbance in Rats and their Offspring

The oxidation of fats and oils is an undisputed subject of science, given the effect of oxidized fats and oils on food quality and safety. This study aimed to determine whether maternal exposure to oxidized soybean oil (OSO) causes lipid metabolism disorders in the liver and whether this lipid metabolism disorder can be transmitted to offspring or even worsened. A total of 60 female Sprague-Dawley (SD) rats were divided randomly into four groups in this study. Treatment groups received a pure diet of OSO with a peroxide value of 200, 400, or 800 mEqO2/kg, while the control group received fresh soybean oil (FSO). As for our results, OSO affected serum biochemical parameters in the maternal generation (F0) and induced liver histopathology changes, inflammation, and oxidative stress. Moreover, the expression of genes related to the liver X receptor α (LXRα)─sterol regulatory element binding protein-1c (SREBP-1c) signaling pathway was changed. Similar trends were found in the livers of offspring on postnatal days 21 and 56. In conclusion, exposure to OSO during gestation and lactation can affect liver lipid synthesis. Additionally, it is detrimental to the development of the offspring's liver, affecting fatty acid metabolism and causing liver damage.

Raspberry polyphenols alleviate neurodegenerative diseases: through gut microbiota and ROS signals

Neurodegenerative diseases are neurological disorders that become more prevalent with age, usually caused by damage or loss of neurons or their myelin sheaths, such as Alzheimer's disease and epilepsy. Reactive oxygen species (ROS) are important triggers for neurodegenerative disease development, and mitigation of oxidative stress caused by ROS imbalance in the human body is important for the treatment of these diseases. As a widespread delicious fruit, the raspberry is widely used in the field of food and medicine because of its abundant polyphenols and other bioactive substances. Polyphenols from a wide variety of raspberry sources could alleviate neurodegenerative diseases. This review aims to summarize the current roles of these polyphenols in maintaining neurological stability by regulating the composition and metabolism of the intestinal flora and the gut-brain axis signal transmission. Especially, we discuss the therapeutic effects on neurodegenerative diseases of raspberry polyphenols through intestinal microorganisms and ROS signals, by means of summary and analysis. Finally, methods of improving the digestibility and utilization of raspberry polyphenols are proposed, which will provide a potential way for raspberry polyphenols to guarantee the health of the human nervous system.

Antioxidant Enzyme System Modulation by Dietary Palm Oils, Palm Kernel Oil and Soybean Oil in Laying Hens

Palm-based oils (palm oil and kernel oil) and soybean oil have unique fatty acid and antioxidant profiles based on the compounds present in them. Hence, this study elucidated the antioxidant properties of crude palm oil (CPO), red palm oil (RPO), refined palm oil (RBD), palm kernel oil (PKO) and soybean oil (SBO) and the influence of dietary oils on blood lipid profiles, tissue fatty acid deposition and the expression of hepatic lipid and lipoprotein metabolism genes in laying hens. The oils were analyzed for color, beta-carotene, free fatty acid and acid value, phenolic content and lipid peroxidation. In an in vivo trial, 150 laying hens were allotted into five groups and supplemented with either CPO, RPO, RBD, PKO or SBO for 16 weeks. High antioxidant compounds present in palm oils help reduce the oxidation of oils. Dietary supplementation with palm oils, particularly CPO and RPO, contributed to the lower liver, serum and jejunal mucosal antioxidant enzyme activities. The antioxidant enzyme genes in the jejunal mucosa were downregulated in palm oils and PKO, but there was no difference between oils in antioxidant enzyme genes in the liver. In conclusion, dietary supplementation with oils with high antioxidant content contributed to protection against oxidation and was associated with a lower requirement for producing antioxidant enzymes.

Manilkara zapota "chicozapote" as a fruit source of health-beneficial bioactive compounds and its effects on chronic degenerative and infectious diseases, a review

Manilkara zapota "chicozapote" is an autochthonous evergreen tree from the Southern regions of Mexico, Belize, and Guatemala. Currently, it is widely distributed and extensively grown in Mexico and Southeast Asia. Traditionally, different structures of the plant have been used for medical purposes; seeds have diuretic and purgative properties, aiding in digestive complications and eliminating bladder and kidney stones. Tree bark has antidiarrheal, antipyretic, antibiotic, and astringent properties. Fruits and leaves have been used to treat cold, cough, diarrhea, indigestion, fever, hemorrhages, wounds, and ulcers. Chicozapote fruit is yellow and brown, with an oval shape and rough peel, it is an excellent source of nutrients, such as sugars, proteins, amino acids, and minerals, and is rich in phytochemical components, such as flavonoids, phenolic acids, and tannins. These bioactive compounds exert several biological activities, i.e., as an antioxidant, antidiabetic, antimicrobial, anti-inflammatory, cytotoxic, and anti-arthritic agents, to name a few. These beneficial properties assist in preventing chronic and degenerative diseases, such as cancer, diabetes, neurological, infectious, and cardiovascular diseases. The use of chicozapote is still limited to its fresh form, and its non-edible structures produce a lot of waste. Therefore, an alternative valorizing and preserving strategy is to use the fruit as a raw source to design functional foods and pharmacological products. Here, the nutritional and phytochemical profiles and the current view regarding methodologies and conditions, for the extraction and characterization of its bioactive compounds, are described, and focus is placed on their multiple biological effects and specific functional mechanisms.

Lipid peroxidation in diamond supported bilayers

Lipid peroxidation is a process that occurs in cells when they are exposed to oxidative stress. During the process reactive oxygen species attack lipids within the lipid bilayers of cells. Since the products of lipid peroxidation are toxic and carcinogenic, it is important to understand where and how it occurs with nanoscale resolution. The radical intermediates of this process are particularly interesting since they are causing chain reactions damaging large parts of the lipid membranes in cells. However, they are also difficult to measure for the state of the art because they are short lived and reactive. Here, we study the lipid peroxidation of three artificial lipid bilayers on a diamonds substrate that can be used to study lipid peroxidation. In particular, we present a diamond quantum sensing method called T₁-relaxometry that allows for in situ measurements and imaging of radical intermediates of lipid peroxidation in these membranes.

Effects of vitrification solution supplemented with platelet-rich plasma in rat ovarian tissue cryopreservation

Background/aim

The subject of this study was to investigate the utility of platelet-rich plasma (PRP) in the cryopreservation process to reduce cryodamage and increase tissue viability.

Materials and methods

Twenty-one female Wistar rats were randomly allocated to three groups. In Group 1 (G1), rats were not subjected to vitrification (n = 7). Group 2 (G2) was the vitrification group in which PRP was added to the basic vitrification solution (n = 7). Group 3 (G3) was the vitrification group in which fetal bovine serum was added to the basic vitrification solution (n = 7). Warmed tissues were evaluated with histochemical (HC) and immunohistochemical (IHC) staining, the TUNEL method, immunofluorescence (IF) staining, and biochemical analyses.

Results

The percentages of IHC staining, TUNEL method positivity, and IF staining were significantly higher in G2 compared to both G1 and G3 (P < 0.05). G2 ovaries exhibited a significant increase in both malondialdehyde and catalase values in comparison to G1 (P < 0.05). In HC staining, degenerations in primary and secondary follicles and in ovarian tissue were more common in the PRP-supplemented group. The calcium used in PRP activation was suspected to have increased the degeneration and prevented the possible positive effects of PRP.

Conclusion

To the best of our knowledge, PRP-supplemented vitrification solution was used for the first time in the literature in this study in whole rat ovarian tissue vitrification. If PRP is to be used as a component in vitrification solution for rat ovarian tissue, the use of lower amounts of calcium or different methods in PRP activation, or the use of nonactivated PRP, should be considered from the beginning.

Advances in transport and toxicity of nanoparticles in plants

In recent years, the rapid development of nanotechnology has made significant impacts on the industry. With the wide application of nanotechnology, nanoparticles (NPs) are inevitably released into the environment, and their fate, behavior and toxicity are indeterminate. Studies have indicated that NPs can be absorbed, transported and accumulated by terrestrial plants. The presence of NPs in certain edible plants may decrease harvests and threaten human health. Understanding the transport and toxicity of NPs in plants is the basis for risk assessment. In this review, we summarize the transportation of four types of NPs in terrestrial plants, and the phytotoxicity induced by NPs, including their impacts on plant growth and cell structure, and the underlying mechanisms such as inducing oxidative stress response, and causing genotoxic damage. We expect to provide reference for future research on the effects of NPs on plants.

Ruscogenin interacts with DPPC and DPPG model membranes and increases the membrane fluidity: FTIR and DSC studies

Ruscogenin, a kind of steroid saponin, has been shown to have significant anti-oxidant, anti-inflammatory, and anti-thrombotic characteristics. Furthermore, it has the potential to be employed as a medicinal medication to treat a variety of acute and chronic disorders. The interaction of a drug molecule with cell membranes can help to elucidate its system-wide protective and therapeutic effects, and it's also important for its pharmacological activity. The molecular mechanism by which ruscogenin affects membrane architecture is still a mystery. Ruscogenin's interaction with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) and anionic dipalmitoyl phosphatidylglycerol (DPPG) multilamellar vesicles (MLVs) was studied utilizing two non-invasive approaches, including: Fourier Transform Infrared (FTIR) spectroscopy and Differential Scanning Calorimetry. Ruscogenin caused considerable alterations in the phase transition profile, order, dynamics and hydration state of head groups and glycerol backbone of DPPC and DPPG MLVs at all concentrations. The DSC results indicated that the presence of ruscogenin decreased the main phase transition temperature (T_m) and enthalpy (ΔH) values of both membranes and increased half height width of the main transition (ΔT_1/2). The FTIR results demonstrated that all concentrations (1, 3, 6, 9, 15, 24 and 30 mol percent) of ruscogenin disordered the DPPC MLVs both in the gel and liquid crystalline phases while it increased the order of DPPG MLVs in the liquid crystalline phase. Moreover, ruscogenin caused an increase in the dynamics of DPPC and DPPG MLVs in both phases. Additionally, it enhanced the hydration of the head groups of lipids and the surrounding water molecules implying ruscogenin to interact strongly with both zwitterionic and charged model membranes.

VANL-100 Attenuates Beta-Amyloid-Induced Toxicity in SH-SY5Y Cells

Antioxidants are being explored as novel therapeutics for the treatment of neurodegenerative diseases such as Alzheimer's disease (AD) through strategies such as chemically linking antioxidants to synthesize novel co-drugs. The main objective of this study was to assess the cytoprotective effects of the novel antioxidant compound VANL-100 in a cellular model of beta-amyloid (Aβ)-induced toxicity. The cytotoxic effects of Aβ in the presence and absence of all antioxidant compounds were measured using the 3-(4,5-dimethylthiazol-2-yl)2-5-diphenyl-2H-tetrazolium bromide (MTT) assay in SH-SY5Y cells in both pre-treatment and co-treatment experiments. In pre-treatment experiments, VANL-100, or one of its parent compounds, naringenin (NAR), alpha-lipoic acid (ALA), or naringenin + alpha-lipoic acid (NAR + ALA), was administrated 24 h prior to an additional 24-h incubation with 20 μM non-fibril or fibril Aβ_25-35. Co-treatment experiments consisted of simultaneous treatment with Aβ and antioxidants. Pre-treatment and co-treatment with VANL-100 significantly attenuated Aβ-induced cell death. There were no significant differences between the protective effects of VANL-100, NAR, ALA, and NAR + ALA with either form of Aβ, or in the effect of VANL-100 between 24-h pre-treatment and co-treatment. These results demonstrate that the novel co-drug VANL-100 is capable of eliciting cytoprotective effects against Aβ-induced toxicity.

Mitigation of Negative Effects of Chromium (VI) Toxicity in Faba Bean (Vicia faba) Plants through the Supplementation of Kinetin (KN) and Gibberellic Acid (GA3)

The present study was carried out to explore the possible role of kinetin and gibberellic acid (GA3) on faba bean under chromium (Cr) stress. Cr treatment negatively affected growth and biomass production, reduced photosynthetic pigments, and inhibited photosynthesis, gas exchange parameters, antioxidant enzymes, and the glyoxylase cycle. Moreover, Cr stress enhanced the production of malondialdehyde (MDA, 216.11%) and hydrogen peroxide (H₂O₂, 230.16%), electrolyte leakage (EL, 293.30%), and the accumulation of proline and glycine betaine. Exogenous application of kinetin and GA3 increased growth and biomass, improved pigment contents and photosynthesis, as well as up-regulated the antioxidant system by improving the antioxidant enzyme activities and the content of nonenzymatic components, and the glyoxylase cycle. Additionally, kinetin and GA3 application displayed a considerable enhancement in proline (602.61%) and glycine betaine (423.72), which help the plants to maintain water balance under stress. Furthermore, a decline in Cr uptake was also observed due to kinetin and GA3 application. Exogenous application of kinetin and GA3 ameliorated the toxic effects of Cr in faba bean plants, up-shooting the tolerance mechanisms, including osmolyte metabolism and the antioxidant system.

Preventive Effects of Mandarin Fruit Peel Hydroethanolic Extract, Hesperidin, and Quercetin on Acetaminophen-Induced Hepatonephrotoxicity in Wistar Rats

Acetaminophen, also known as N-acetyl-para-aminophenol (NAPAP), is a traditional antipyretic and analgesic that is used extensively around the world to treat colds and fevers. However, a NAPAP excess causes rapid, severe liver and kidney damage. The goal of the study was to examine the protective effects and determine the mechanisms of action of MPHE, hesperidin, and quercetin in NAPAP-induced hepatorenal damage in Wistar rats. Male Wistar rats received a 0.5 g/kg oral supplement of NAPAP every other day for a period of four weeks. During the same period of NAPAP supplementation, MPHE (50 mg/kg), quercetin (20 mg/kg), and hesperidin (20 mg/kg) were administered to rats receiving NAPAP. MPHE, quercetin, and hesperidin treatments significantly improved liver function in NAPAP-supplemented rats. The high serum levels of aminotransferases, alkaline phosphatase, lactate dehydrogenase, and γ-glutamyl transferase as well as total bilirubin were significantly reduced, while the levels of suppressed serum albumin were significantly increased, demonstrating this improvement. Treatments utilizing these natural substances significantly enhanced kidney function as seen by a considerable decline in the increased blood levels of urea, uric acid, and creatinine. Additionally, the injection of MPHE, hesperidin, and quercetin resulted in a decrease in the quantity of lipid peroxides while increasing the activities of superoxide dismutase, glutathione peroxidase, and glutathione-S-transferase in the liver and kidneys. The treatments markedly abated the NAPAP-induced liver and kidney histological perturbations and reduced the NAPAP-induced serum tumor necrosis factor-α level and liver and kidney proapoptotic protein 53 and caspase 3 expressions. Otherwise, serum interleukin-4 level significantly increased by treatments. The MPHE, hesperidin, and quercetin treatments resulted in marked decrease in liver and kidney histopathological scores including inflammation, necrosis, apoptosis, and congestion. In conclusion, the MPHE, quercetin, and hesperidin may induce hepatonephropreventive impacts in NAPAP-supplemented rats via enhancing the antioxidant defense system, anti-inflammatory activity, and antiapoptotic action.

Mechanistic Understanding from Molecular Dynamics in Pharmaceutical Research 2: Lipid Membrane in Drug Design

We review the use of molecular dynamics (MD) simulation as a drug design tool in the context of the role that the lipid membrane can play in drug action, i.e., the interaction between candidate drug molecules and lipid membranes. In the standard "lock and key" paradigm, only the interaction between the drug and a specific active site of a specific protein is considered; the environment in which the drug acts is, from a biophysical perspective, far more complex than this. The possible mechanisms though which a drug can be designed to tinker with physiological processes are significantly broader than merely fitting to a single active site of a single protein. In this paper, we focus on the role of the lipid membrane, arguably the most important element outside the proteins themselves, as a case study. We discuss work that has been carried out, using MD simulation, concerning the transfection of drugs through membranes that act as biological barriers in the path of the drugs, the behavior of drug molecules within membranes, how their collective behavior can affect the structure and properties of the membrane and, finally, the role lipid membranes, to which the vast majority of drug target proteins are associated, can play in mediating the interaction between drug and target protein. This review paper is the second in a two-part series covering MD simulation as a tool in pharmaceutical research; both are designed as pedagogical review papers aimed at both pharmaceutical scientists interested in exploring how the tool of MD simulation can be applied to their research and computational scientists interested in exploring the possibility of a pharmaceutical context for their research.

Dimeric Histidine as a Novel Free Radical Scavenger Alleviates Non-Alcoholic Liver Injury

Non-alcoholic liver injury (NLI) is a common disease worldwide. Since free radical damage in the liver is a crucial initiator leading to diseases, scavenging excess free radicals has become an essential therapeutic strategy. To enhance the antioxidant capacity of histidine, we synthesized a protonated dimeric histidine, H-bihistidine, and investigated its anti-free radical potential in several free-radical-induced NLI. Results showed that H-bihistidine could strongly scavenge free radicals caused by H₂O₂, fatty acid, and CCl₄, respectively, and recover cell viability in cultured hepatocytes. In the animal model of nonalcoholic fatty liver injury caused by high-fat diet, H-bihistidine reduced the contents of transaminases and lipids in serum, eliminated the liver’s fat accumulation, and decreased the oxidative damage. Moreover, H-bihistidine could rescue CCl₄-induced liver injury and recover energy supply through scavenging free radicals. Moreover, liver fibrosis prepared by high-fat diet and CCl₄ administration was significantly alleviated after H-bihistidine treatment. This study suggests a novel nonenzymatic free radical scavenger against NLI and, potentially, other free-radical-induced diseases.

Myricetin prevents high molecular weight Aβ1-42 oligomer-induced neurotoxicity through antioxidant effects in cell membranes and mitochondria

Excessive accumulation of amyloid β-protein (Aβ) is one of the primary mechanisms that leads to neuronal death with phosphorylated tau in the pathogenesis of Alzheimer's disease (AD). Protofibrils, one of the high-molecular-weight Aβ oligomers (HMW-Aβo), are implicated to be important targets of disease modifying therapy of AD. We previously reported that phenolic compounds such as myricetin inhibit Aβ1-40, Aβ1-42, and α-synuclein aggregations, including their oligomerizations, which may exert protective effects against AD and Parkinson's disease. The purpose of this study was to clarify the detailed mechanism of the protective effect of myricetin against the neurotoxicity of HMW-Aβo in SH-SY5Y cells. To assess the effect of myricetin on HMW-Aβo-induced oxidative stress, we systematically examined the level of membrane oxidative damage by measuring cell membrane lipid peroxidation, membrane fluidity, and cell membrane potential, and the mitochondrial oxidative damage was evaluated by mitochondrial permeability transition (MPT), mitochondrial reactive oxygen species (ROS), and manganese-superoxide dismutase (Mn-SOD), and adenosine triphosphate (ATP) assay in SH-SY5Y cells. Myricetin has been found to increased cell viability by suppression of HMW-Aβo-induced membrane disruption in SH-SY5Y cells, as shown in reducing membrane phospholipid peroxidation and increasing membrane fluidity and membrane resistance. Myricetin has also been found to suppress HMW-Aβo-induced mitochondria dysfunction, as demonstrated in decreasing MPT, Mn-SOD, and ATP generation, raising mitochondrial membrane potential, and increasing mitochondrial-ROS generation. These results suggest that myricetin preventing HMW-Aβo-induced neurotoxicity through multiple antioxidant functions may be developed as a disease-modifying agent against AD.

Role of Quercetin in Depressive-Like Behaviors: Findings from Animal Models

Depressive-like behavior is a highly prevalent worldwide neuropsychiatric disorder that owns a complex pathophysiologic mechanism. The available pharmacotherapy is ineffective for most patients and shown several adverse effects. Therefore, it is important to find efficacy and safe antidepressive compounds. Some phytochemicals compounds regulate the same genes and pathways targeted by drugs; therefore, diets rich in fruits and vegetables could be considered novel treatment approaches. Currently, the functional properties of quercetin acquired great interest, due to its beneficial effects on health. Quercetin is a flavonoid ubiquitously present in vegetables and fruits, interestingly for its strong antioxidant properties. The purpose of this review is to summarize the preclinical studies present in the literature, in the last ten years, aimed at illustrating the effects of quercetin pre-treatment in depressive-like behaviors. Quercetin resulted in antidepressant-like actions due to its antioxidant, anti-inflammatory, and neuroprotective effects. This pointed out the usefulness of this flavonoid as a nutraceutical compound against the development of psychological stress-induced behavioral perturbation. Therefore, quercetin or a diet containing it may become a prospective supplementation or an efficient adjuvant therapy for preventing stress-mediated depressive-like behavior.

Selenium Biofortification of Soybean Seeds Influences Physiological Responses of Seedlings to Osmotic Stress

Climate change poses a serious threat to agricultural production. Water deficit in agricultural soils is one of the consequences of climate change that has a negative impact on crop growth and yield. Selenium (Se) is known to be involved in plant defense against biotic and abiotic stress through metabolic, structural, and physiological activity in higher plants. The aim of this study was to investigate the physiological response of Se-biofortified soybean (Glycine max (L.) Merrill) seedlings under osmotic stress. For this research, we used biofortified soybean grain obtained after foliar Se biofortification in 2020. The experiment was conducted in a growth chamber with two cultivars (Lucija and Sonja) grown on filter paper in three replicates. The experiment was carried out with two watering treatments: distilled water (PEG-0) and 2.5% polyethylene glycol 6000 (PEG-2.5) on Se-biofortified seeds (Se) and nonbiofortified seeds (wSe). Contents of lipid peroxidation product (LP), free proline (PRO), total phenolic content (TP), ferric reducing antioxidant power (FRAP), and ascorbic acid (AA) were analyzed in 7-days-old seedlings. Significant differences were detected in the Se content of soybean grains between the two cultivars. A milder reaction to PEG-2.5 was observed in cultivar Lucija in both Se and wSe treatments, which might represent the mitigating effects of Se on osmotic stress in this cultivar. Contrarily, in cultivar Sonja, Se adversely affected all analyzed traits in the PEG-2.5 treatment. Ultimately, Se is a pro-oxidant in Sonja, whereas it represents an anti-oxidant in Lucija. In conclusion, different soybean cultivars show contrasting physiological reactions to both osmotic stress and Se. However, the activation of antioxidant pathways in Sonja can also be interpreted as added value in soybean seedlings as a functional food.

Comparison of coenzyme Q10 or fish oil for prevention of intermittent hypoxia-induced oxidative injury in neonatal rat lungs

BACKGROUND

Neonatal intermittent hypoxia (IH) results in oxidative distress in preterm infants with immature antioxidant systems, contributing to lung injury. Coenzyme Q10 (CoQ10) and fish oil protect against oxidative injury. We tested the hypothesis that CoQ10 is more effective than fish oil for prevention of IH-induced lung injury in neonatal rats.

METHODS

Newborn rats were exposed to two clinically relevant IH paradigms at birth (P0): (1) 50% O₂ with brief hypoxia (12% O₂); or (2) room air (RA) with brief hypoxia (12% O₂), until P14 during which they were supplemented with daily oral CoQ10, fish oil, or olive oil from P0 to P14. Pups were studied at P14 or placed in RA until P21 with no further treatment. Lungs were assessed for histopathology and morphometry; biomarkers of oxidative stress and lipid peroxidation; and antioxidants.

RESULTS

Of the two neonatal IH paradigms 21%/12% O₂ IH resulted in the most severe outcomes, evidenced by histopathology and morphometry. CoQ10 was effective for preserving lung architecture and reduction of IH-induced oxidative stress biomarkers. In contrast, fish oil resulted in significant adverse outcomes including oversimplified alveoli, hemorrhage, reduced secondary crest formation and thickened septae. This was associated with elevated oxidants and antioxidants activities.

CONCLUSIONS

Data suggest that higher FiO₂ may be needed between IH episodes to curtail the damaging effects of IH, and to provide the lungs with necessary respite. The negative outcomes with fish oil supplementation suggest oxidative stress-induced lipid peroxidation.

Antioxidant Synergy of Mitochondrial Phospholipase PNPLA8/iPLA2γ with Fatty Acid-Conducting SLC25 Gene Family Transporters

Patatin-like phospholipase domain-containing protein PNPLA8, also termed Ca²⁺-independent phospholipase A2γ (iPLA2γ), is addressed to the mitochondrial matrix (or peroxisomes), where it may manifest its unique activity to cleave phospholipid side-chains from both sn-1 and sn-2 positions, consequently releasing either saturated or unsaturated fatty acids (FAs), including oxidized FAs. Moreover, iPLA2γ is directly stimulated by H₂O₂ and, hence, is activated by redox signaling or oxidative stress. This redox activation permits the antioxidant synergy with mitochondrial uncoupling proteins (UCPs) or other SLC25 mitochondrial carrier family members by FA-mediated protonophoretic activity, termed mild uncoupling, that leads to diminishing of mitochondrial superoxide formation. This mechanism allows for the maintenance of the steady-state redox status of the cell. Besides the antioxidant role, we review the relations of iPLA2γ to lipid peroxidation since iPLA2γ is alternatively activated by cardiolipin hydroperoxides and hypothetically by structural alterations of lipid bilayer due to lipid peroxidation. Other iPLA2γ roles include the remodeling of mitochondrial (or peroxisomal) membranes and the generation of specific lipid second messengers. Thus, for example, during FA β-oxidation in pancreatic β-cells, H₂O₂-activated iPLA2γ supplies the GPR40 metabotropic FA receptor to amplify FA-stimulated insulin secretion. Cytoprotective roles of iPLA2γ in the heart and brain are also discussed.

Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper

Oxidative stress (OS) induced by the disturbed homeostasis of metal ions is one of the pivotal factors contributing to neurodegeneration. The aim of the present study was to investigate the effects of flavonoid myricetin on copper-induced toxicity in neuroblastoma SH-SY5Y cells. As determined by the MTT method, trypan blue exclusion assay and measurement of ATP production, myricetin heightened the toxic effects of copper and exacerbated cell death. It also increased copper-induced generation of reactive oxygen species, indicating the prooxidative nature of its action. Furthermore, myricetin provoked chromatin condensation and loss of membrane integrity without caspase-3 activation, suggesting the activation of both caspase-independent programmed cell death and necrosis. At the protein level, myricetin-induced upregulation of PARP-1 and decreased expression of Bcl-2, whereas copper-induced changes in the expression of p53, p73, Bax and NME1 were not further affected by myricetin. Inhibitors of ERK1/2 and JNK kinases, protein kinase A and L-type calcium channels exacerbated the toxic effects of myricetin, indicating the involvement of intracellular signaling pathways in cell death. We also employed atomic force microscopy (AFM) to evaluate the morphological and mechanical properties of SH-SY5Y cells at the nanoscale. Consistent with the cellular and molecular methods, this biophysical approach also revealed a myricetin-induced increase in cell surface roughness and reduced elasticity. Taken together, we demonstrated the adverse effects of myricetin, pointing out that caution is required when considering powerful antioxidants for adjuvant therapy in copper-related neurodegeneration.

Use of Spectroscopic Techniques to Monitor Changes in Food Quality during Application of Natural Preservatives: A Review

Consumer demand for food of high quality has driven research for alternative methods of food preservation on the one hand, and the development of new and rapid quality assessment techniques on the other hand. Recently, there has been a growing need and interest in healthier food products, which has led to an increased interest in natural preservatives, such as essential oils, plant extracts, and edible films and coatings. Several studies have shown the potential of using biopreservation, natural antimicrobials, and antioxidant agents in place of other processing and preservation techniques (e.g., thermal and non-thermal treatments, freezing, or synthetic chemicals). Changes in food quality induced by the application of natural preservatives have been commonly evaluated using a range of traditional methods, including microbiology, sensory, and physicochemical measurements. Several spectroscopic techniques have been proposed as promising alternatives to the traditional time-consuming and destructive methods. This review will provide an overview of recent studies and highlight the potential of spectroscopic techniques to evaluate quality changes in food products following the application of natural preservatives.