Cell Membrane Lipid Peroxidation Research Articles

Silicon alleviates autotoxicity by regulating membrane lipid peroxidation and improving photosynthetic efficiency in cucumber seedlings (Cucumis sativus L.)

Autotoxicity is one of the main causes of cucumber continuous cropping obstacles. Cinnamic acid (CA), a phenolic acid derivative, acts as an autotoxin found in cucumber root exudates. The autotoxicity mimicked by CA significantly increases membrane lipid peroxidation in root and leaf cells, resulting in damage to the structure and function of root tip cells and leaf cells. It also injures the activity of photosystem PSII, reducing the photosynthetic rate and inhibiting the growth of cucumber plants. Supplementing Si alleviates CA-mimicked autotoxicity by increasing the thickness and smoothness of root tip cell walls, inhibiting the absorption and accumulation of CA, as well as relieving osmotic stress and membrane lipid peroxidation caused by CA in cucumber roots and leaves. Additionally, Si promotes grana lamella (GL) stacking and increases thylakoid numbers in chloroplasts. It also enhances the chlorophyll content in cucumber leaves and improves the energy conversion efficiency of photosystem PSII. These effects lead to an improvement in both photosynthetic efficiency and dry matter accumulation, as well as increased the resistance to CA-induced autotoxicity in cucumber plants. The same concentration of Si had no significant effect on the growth of cucumber seedlings, indicating that Si plays an important role in improving the tolerance to autotoxicity in cucumbers. These findings provide an effective theoretical basis and methods for research regarding the alleviation of continuous cropping obstacles.

Photodynamic Therapy Combined with Ferroptosis Is a Synergistic Antitumor Therapy Strategy.

Ferroptosis is a programmed death mode that regulates redox homeostasis in cells, and recent studies suggest that it is a promising mode of tumor cell death. Ferroptosis is regulated by iron metabolism, lipid metabolism, and intracellular reducing substances, which is the mechanism basis of its combination with photodynamic therapy (PDT). PDT generates reactive oxygen species (ROS) and 1O2 through type I and type II photochemical reactions, and subsequently induces ferroptosis through the Fenton reaction and the peroxidation of cell membrane lipids. PDT kills tumor cells by generating excessive cytotoxic ROS. Due to the limited laser depth and photosensitizer enrichment, the systemic treatment effect of PDT is not good. Combining PDT with ferroptosis can compensate for these shortcomings. Nanoparticles constructed by photosensitizers and ferroptosis agonists are widely used in the field of combination therapy, and their targeting and biological safety can be improved through modification. These nanoparticles not only directly kill tumor cells but also further exert the synergistic effect of PDT and ferroptosis by activating antitumor immunity, improving the hypoxia microenvironment, and inhibiting the tumor angiogenesis. Ferroptosis-agonist-induced chemotherapy and PDT-induced ablation also have good clinical application prospects. In this review, we summarize the current research progress on PDT and ferroptosis and how PDT and ferroptosis promote each other.

Synthesis, properties and mechanism of carbon dots-based nano-antibacterial materials.

Antibiotics play an important role in the treatment of diseases, but bacterial resistance caused by their widespread and unreasonable use has become an urgent problem in clinical treatment. With the rapid advancement of nanoscience and nanotechnology, the development of nanomedicine has been transformed into a new approach to the problem of bacterial resistance. As a new type of carbon-based nanomaterial, carbon dots (CDs) have attracted the interest of antibacterial researchers due to their ease of preparation, amphiphilicity, facile surface functionalization, and excellent optical properties, among other properties. This article reviewed the synthesis methods and properties of various CDs and their composites in order to highlight the advancements in the field of CDs-based antibacterial agents. Then we focused on the relationship between the principal properties of CDs and the antibacterial mechanism, including the following: (1) the physical damage caused by the small size, amphiphilicity, and surface charge of CDs. (2) Photogenerated electron transfer characteristics of CDs that produce reactive oxygen species (ROS) in themselves or in other compounds. The ability of ROS to oxidize can lead to the lipid peroxidation of cell membranes, as well as damage proteins and DNA. (3) The nano-enzyme properties of CDs can catalyze reactions that generate ROS. (4) Synergistic antibacterial effect of CDs and antibiotics or other nanocomposites. Finally, we look forward to the challenges that CDs-based nanocomposites face in practical antibacterial applications and propose corresponding solutions to further expand the application potential of nanomaterials in the treatment of infectious diseases, particularly drug-resistant bacterial infections.

Low-Dose Exposure of WS2 Nanosheets Induces Differential Apoptosis in Lung Epithelial Cells.

Escalating the production and application of tungsten disulfide (WS2) nanosheets inevitably increases environmental human exposure and warrants the necessity of studies to elucidate their biological impacts. Herein, we assessed the toxicity of WS2 nanosheets and focused on the impacts of low doses (≤10 μg/mL) on normal (BEAS-2B) and tumorigenic (A549) lung epithelial cells. The low doses, which approximate real-world exposures, were found to induce cell apoptosis, while doses ≥ 50 μg/mL cause necrosis. Focused studies on low-dose exposure to WS2 nanosheets revealed more details of the impacts on both cell lines, including reduction of cell metabolic activity, induction of lipid peroxidation in cell membranes, and uncoupling of mitochondrial oxidative phosphorylation that led to the loss of ATP production. These phenomena, along with the expression situations of a few key proteins involved in apoptosis, point toward the occurrence of mitochondria-dependent apoptotic signaling in exposed cells. Substantial differences in responses to WS2 exposure between normal and tumorigenic lung epithelial cells were noticed as well. Specifically, BEAS-2B cells experienced more adverse effects and took up more nanosheets than A549 cells. Our results highlight the importance of dose and cell model selection in the assessment of nanotoxicity. By using doses consistent with real-world exposures and comparing normal and diseased cells, we can gain knowledge to guide the development of safety precautions for mitigating the adverse impacts of nanomaterial exposure on human health.

Polypropylene/Poly(butylene adipate-co-terephthalate) Breathing Film for Inhibiting Pseudomonas and Maintaining Microbial Communities and Postharvest Quality of Allium mongolicum Regel during Storage.

Allium mongolicum Regel (A. mongolicum) is a healthy edible plant but highly perishable with a short shelf life of 1-2 d. Modified atmosphere packaging (MAP) could inhibit the postharvest senescence and decay of the vegetables. Thus, the aim of this study was to apply MAP with different gas permeabilities to the storage of A. mongolicum and evaluate its effects on maintaining microbial communities and the postharvest quality of A. mongolicum. The results showed that polypropylene/poly(butylene adipate-co-terephthalate) (PP/PBAT, abbreviated as PAT) MAP was suitable for the storage of A. mongolicum by establishing an optimal atmosphere of 0.5-0.6% O2 and 6.2-7.1% CO2 in the bag. It could delay the postharvest senescence of A. mongolicum and maintain its quality by slowing down its respiration rate and weight loss, reducing cell membrane permeability and lipid peroxidation, maintaining the cell wall, and reducing infection and the growth of microorganisms. However, A. mongolicum in HPT was more perishable than that in PAT during storage. Pseudomonas was found to be the main spoilage bacteria, and they could also be effectively inhibited by PAT-MAP. The next-generation sequencing results also showed the growth of Escherichia-Shigella, Clostridium sensu stricto 1, Streptococcus, Aureobasidium, Didymella, and Fusarium, responsible for A. mongolicum decay or human disease, was well inhibited by PAT-MAP. The results suggested that PAT-MAP could be used to maintain microbial diversity and the postharvest quality of A. mongolicum under cold storage conditions. It provided a feasible solution for the preservation, food quality, and safety control of A. mongolicum.

Is There an Association Between Dietary Antioxidant Levels and Sperm Parameters in Male Infertility?

Oxidative stress is known as a mechanism underlying male infertility; it is defined as an imbalance between pro-oxidants and antioxidants leading to DNA damage, peroxidation of plasma membrane lipids, and protein oxidation.This study was conducted to investigate the relationship between total antioxidant capacity and sperm parameters in male infertility. A total of 187 men with infertility (asthenospermia group (n=51), oligospermia group (n=40), and control group (n=96) were included in the current study. The following risk factors were recorded: age, sperm volume, sperm motility, hormone levels, and dietary antioxidant content. Demographic parameters and hormone levels of cases showed no statistically significant difference between groups (p > 0.05). Semen volume, motility, vitamin A, retinol, vitamin D, and vitamin C levels were statistically significantly lower in the asthenospermia and oligospermia groups (p < 0.05). According to the logistic regression model, lower vitamin A, retinol, vitamin D, and vitamin C levels were risk factors for poor sperm outcomes (p < 0.001). Conclusıon: Male infertility with poor sperm outcomes should have an assessment of antioxidant capacity and nutritional specialization including food high in antioxidants could improve sperm parameters in asthenospermia and oligospermia and it could be used for therapeutic opportunities.

Biomacromolecular and Toxicity Responses of Bacteria upon the Nano-Bio Interfacial Interactions with Ti3C2Tx Nanosheets.

The biomolecular responses of bacteria to 2D nanosheets that result from nano-bio interfacial interactions remain to be thoroughly examined. Herein, Fourier transform infrared (FTIR) multivariate and 2D correlation analyses were performed to assess the composition and conformational changes in bacterial biomacromolecules (lipids, polysaccharides, and carbohydrates) upon exposure to Ti3C2Tx nanosheets. General toxicity assays, 3D excitation-emission matrix fluorescence analyses, extended Derjaguin-Landau-Verwey-Overbeek theory interaction calculations, and isothermal titration calorimetry were also performed. Our results demonstrate that Ti3C2Tx nanosheets considerably impact Gram-positive bacteria (Bacillus subtilis), causing oxidative damage and inactivation by preferentially interacting with and disrupting the cell walls. The bilayer membrane structure of Gram-negative bacteria (Escherichia coli) endows them with increased resistance to Ti3C2Tx nanosheets. The unmodified nanosheets had a higher affinity to bacterial protein components with lower toxicity due to their susceptibility to oxidation. Surface modification with KOH or hydrazine (HMH), particularly HMH, induced stronger dispersion, antioxidation, and affinity to bacterial phospholipids, which resulted in severe cell membrane lipid peroxidation and bacterial inactivation. These findings provide valuable insight into nano-bio interfacial interactions, which can facilitate the development of antimicrobial and antifouling surfaces and contribute to the evaluation of the environmental risks of nanomaterials.

Abstract P1156: Potential Role Of Ferroptosis In Duchenne Muscular Dystrophy-associated Cardiomyopathy

Background and Aims: Duchenne muscular dystrophy (DMD) is the most common and fatal form of muscular dystrophy. DMD-associated cardiomyopathy (DMD-CM) is a major cause of morbidity and mortality in patients with DMD. Ferroptosis, a new type of regulated cell death characterized by iron-dependence and the accumulation of cell membrane lipid peroxidation, has been manifested in various cardiovascular disease conditions. However, ferroptosis has not been studied in DMD-CM. Here, we aim to determine whether ferroptosis play a potential role in DMD-CM. Methods and Results: We used a dystrophin/utrophin double knockout (mdx:utr -/- ) mouse model that displays clinical signs of DMD and DMD-CM. We performed RNA isolation from the ventricles of 3-month-old wild type (WT) and mdx:utr -/- mice (n=3) and performed RNA-Seq analysis. We found alterations of ferroptosis-related pathways such as GTP cyclohydrolase 1, transferrin receptor, glutamine transporter SLC38A1, heme oxygenase-1 (HMOX-1), and arachidonate 5-lipoxygenase (ALOX5) pathways in mdx:utr -/- hearts compared to WT hearts. Western blots confirmed the upregulation of ALOX5 and downregulation of HMOX-1, ferroptosis suppressor protein 1, and NADPH oxidase 4 in mdx:utr -/- hearts, while there was no change in glutathione peroxidase 4 (GPX4) levels. We also observed an increased level of lipid peroxidation in mdx:utr -/- hearts compared to WT as estimated by the level of malondialdehyde. Live/dead viability assays demonstrated a higher cell death rate in cardiomyocytes from mdx:utr -/- mice (53.7±7.2%, n=24) compared to those from WT mice (11.7±1.1%, n=17, p&lt; 0.01) under control conditions. The observed cell death in mdx:utr -/- cardiomyocytes was efficiently prevented by the selective ferroptosis inhibitor ferrostatin-1 (10 μM) (7.4±1.5%, n=9, p&lt;0.01), but not by the apoptosis inhibitor emricasan (20 μM) (56.0±1.6%, n=3, NS). Similarly, higher death rates were also observed in mdx:utr -/- than in WT cardiomyocytes when they were treated with various ferroptosis inducers such as iron overload and the GPX4 inhibitor RSL3. Conclusion: We have deciphered the link between ferroptosis and DMD-CM for the first time. Our data suggest novel targets for the treatment of DMD-CM by inhibiting ferroptosis.

Antioxidant and Anti-inflammatory Activities Mediate the Radioprotective Effect of Trianthema portulacastrum L. Extracts

Background: Ionizing radiation (IR) generates reactive oxygen species (ROS), which leads to oxidative stress that often leads to inflammatory responses in organisms. Objective: Trianthema portulacastrum L., a plant commonly growing in India, is rich in antioxidant phytochemicals. This is responsible for scavenging free radicals and may provide radioprotective and anti-inflammatory effects in response to ionizing radiation. Methods: The effect of T. portulacastrum extracts was studied in hepatic cells, which are susceptible to radiation-induced damage and in macrophages, which are the primary inflammatory cells of the body. Results: T. portulacastrum stem extracts showed efficient free radical scavenging activity in hepatocytes and decreased radiation-induced lipid peroxidation in cell and mitochondrial membranes. Treatment of irradiated cells with T. portulacastrum stem extracts enhanced cell viability at lower concentration and reduced cell viability at higher concentration. Treatment with low concentration of T. portulacastrum stem extract also reduced cellular ROS generation and increased the concentration of cellular anti-oxidant, glutathione. T. portulacastrum extracts also showed remarkable anti-inflammatory properties in macrophages activated by the inflammatory agonist bacterial lipopolysaccharide (LPS). The extract reduced nitric oxide (NO) production and suppressed the expression of inflammatory genes. Conclusion: Together, these observations demonstrated a potential radioprotective role of T. portulacastrum extract mediated by both its antioxidant activity on hepatic epithelial cells and its anti-inflammatory activity on immune cells.

Melatonin Preserves Fluidity in Cell and Mitochondrial Membranes against Hepatic Ischemia-Reperfusion.

We evaluated the in vivo effects of melatonin treatment on oxidative damage in the liver in an experimental model of ischemia-reperfusion. A total of 37 male Sprague-Dawley rats were randomly divided into four groups: control, ischemia, ischemia + reperfusion, and ischemia + reperfusion + melatonin. Hepatic ischemia was maintained for 20 min, and the clamp was removed to initiate vascular reperfusion for 30 min. Melatonin (50 mg/kg body weight) was intraperitoneally administered. Fluidity was measured by polarization changes in 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene-p-toluene sulfonate). After 20 min of ischemia, no significant changes were observed in cell and mitochondrial membrane fluidity levels, lipid peroxidation, and protein carbonylation. However, after 30 min of reperfusion, membrane fluidity decreased compared to controls. Increases in lipid and protein oxidation were also seen in hepatic homogenates of animals exposed to reperfusion. Melatonin injected 30 min before ischemia and reperfusion fully prevented membrane rigidity and both lipid and protein oxidation. Livers from ischemia-reperfusion showed histopathological alterations and positive labeling with antibodies to oxidized lipids and proteins. Melatonin reduced the severity of these morphological changes and protected against in vivo ischemia-reperfusion-induced toxicity in the liver. Therefore, melatonin might be a candidate for co-treatment for patients with hepatic vascular occlusion followed by reperfusion.

Inactivation of Salmonella using ultrasound in combination with Litsea cubeba essential oil nanoemulsion and its bactericidal application on cherry tomatoes

The presence of Salmonella in nature poses a significant and unacceptable threat to the human public health domain. In this study, the antibacterial effect and mechanism of ultrasound (US) combined with Litsea cubeba essential oil nanoemulsion (LEON) on Salmonella. LEON + US treatment has a significant bactericidal effect on Salmonella. Reactive oxygen species (ROS), malondialdehyde (MDA) detection, N-phenyl-l-naphthylamine (NPN) uptake and nucleic acid release assays showed that LEON + US exacerbated cell membrane lipid peroxidation and increased the permeability of the cell membrane. The results of field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) showed that LEON + US treatment was able to alter cell morphology. It can be observed by flow cytometry (FCM) that LEON + US treatment can cause cell apoptosis. In addition, bacterial counts of cherry tomatoes treated with LEON (0.08 μL/mL) + US (345 W/cm2) for 9 min were reduced by 6.50 ± 0.20 log CFU/mL. This study demonstrates that LEON + US treatment can be an effective way to improve the safety of fruits and vegetables in the food industry.

Trigger Mechanisms of Cypermethrin-Induced Changes of Metabolism: An Experimental Study

Background: The purpose of this work was to study the triggering mechanisms of metabolic changes in experimental animals after a single injection of cypermethrin at a dose of 55 mg/kg of body weight. Methods and Results: Sixty rats were randomly divided into four groups (15 rats in each group). Rats of the control groups (G1 and G3) were injected with saline into the stomach. Animals of the experimental groups (G2 and G4) were injected once with the synthetic pyrethroid cypermethrin at a dose of 55 mg/kg of body weight, which is 1/5 LD50. Before being withdrawn from the experiment, blood was taken in vivo under anesthesia, and the liver was removed. The glucose, lactate, uric acid, and total bilirubin concentrations were determined in blood serum by unified research methods. The content of glutathione (GSH), malondialdehyde (MDA), and activity of glucose-6-phosphate dehydrogenase (G6PDH) was determined in erythrocyte hemolysates. In liver homogenates, the content of total protein, glycogen, uric acid, and inorganic phosphorus (Pi) was determined by unified methods, as well as MDA, GSH, activity of G6PDH, microsomal oxygenase, glutathione-S-transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR). Administration of cypermethrin to laboratory rats at a dose of 1/5 LD50 causes adaptive changes in metabolism. After one day, there was an increase in the content of glucose in the blood serum against the background of a deficiency of carbohydrates in the liver tissue. At the same time, there was an increase in anaerobic oxidation and an increase in purine catabolism, which was associated with the activation of lipid peroxidation (LP) of cell membranes and the depletion of the pool of antioxidants. GSH deficiency was exacerbated by an increase in the activity of antioxidant enzymes and xenobiotic biotransformation systems. Seven days after the administration of cypermethrin, rats retained a high rate of breakdown of purines to uric acid. This process was enhanced by a decrease in the RBC, a deficiency of carbohydrates, and inhibition of the activity of G6PDH, GPx, and GR. This ultimately led to the development of oxidative stress. Conclusion: The triggers for the development of oxidative stress under cypermethrin exposure are lactic acidosis and increased catabolism of purine mononucleotides, accompanied by an increase in the production of free radicals and inhibition of the function of the antioxidant system. A decrease in the blood RBC, carbohydrate deficiency, and suppression of the activity of the pentose cycle 7 days after the administration of cypermethrin aggravate this condition.

Moderate nitrogen application improved salt tolerance by enhancing photosynthesis, antioxidants, and osmotic adjustment in rapeseed (Brassica napus L.).

Salt stress is a major adverse environmental factor limiting plant growth. Nitrogen (N) application is an effective strategy to alleviate the negative effects of salt stress on plants. To improve the knowledge of the mechanism of N application on alleviating salt stress on rapeseed seedlings, a pot experiment was conducted with four N application treatments (0, 0.1, 0.2, and 0.3g N kg-1 soil, referred to as N0, N1, N2, and N3, respectively) and exposed to non-salt stress (0g NaCl kg-1 soil, referred to as S0) and salt stress (3g NaCl kg-1 soil, referred to as S1) conditions. The results indicated that in comparison with non-salt stress, salt stress increased the Na content (236.53%) and reactive oxygen species (ROS) production such as hydrogen peroxide (H2O2) (30.26%), resulting in cell membrane lipid peroxidation characterized by an increased content of malondialdehyde (MDA) (122.32%) and suppressed photosynthetic rate (15.59%), finally leading to inhibited plant growth such as shorter plant height, thinner root neck, lower leaf area, and decreased dry weight. N application improved the plant growth, and the improvement by N application under salt stress was stronger than that under non-salt stress, suggesting that rapeseed seedlings exposed to salt stress are more sensitive to N application and require N to support their growth. Moreover, seedlings exposed to salt stress under N application showed lower ROS accumulation; increased photosynthesis; higher antioxidants such as catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), and ascorbic acid (AsA); and greater accumulation of osmotic substances including soluble protein, soluble sugar, and proline, as compared with seedlings without N application. In particular, the best improvement by N application under salt stress occurred at the N2 level, while too high N application could weaken the improvement due to inhibited N metabolism. In summary, this study suggests that moderate N application can improve photosynthesis, antioxidants, and osmoregulation to alleviate the adverse effects of salt stress in rapeseed seedlings.

Inhibitory effect of ε-poly-L-lysine on fruit Colletotrichum gloeosporioides through regulating organic acid metabolism and exerting membrane-targeted antifungal activity

Colletotrichum gloeosporioides (C. gloeosporioides) is the eighth harmful fungus among the top ten fungal pathogens in plant pathology, and the anthrax is a highly infectious disease caused by it. More efficient and environmental-friendly biological fungicide is needed to control anthrax. This study analyzed the inhibition mechanism of ε-poly-L-lysine (ε-PL) on C. gloeosporioides from the perspective of organic acid metabolism and membrane targeting. The results showed that ε-PL had a better inhibitory effect on C. gloeosporioides in vitro than commonly used chlorine source fungicides, such as chlorine dioxide and sodium hypochlorite. In vivo study, it was found that ε-PL reduced the expansion of anthracnose in winter jujube, fig, mango, tomato, apple and pitaya fruit. In addition, ε-PL had a remarkable impact on spore germination, germ tube elongation, mycelia morphology，and hypha density of C. gloeosporioides. From aspect of membrane targeting, ε-PL treatment destroyed the cell membrane of C. gloeosporioides, causing leakage of cell contents, lipid peroxidation of cell membrane and damage of mitochondria. In addition, from the results of pH and total acid determination, the pH of the control group decreased from 5.72 to 4.71, and the total acid content increased by 8.4 g L−1. High-Performance Liquid Chromatography (HPLC) results showed that C. gloeosporioides mainly producing malic acid, and its content accounted for 58.46% of the total organic acid, followed by citric acid, lactic acid and succinic acid. After 96 h of culture, the contents of four acids in 400 mg L−1 group were inhibited by 71.50%, 6.25%, 14.71% and 100% respectively, compared with the control group. The above results showed that ε-PL could play a remarkable antifungal role by causing membrane damage of C. gloeosporioides and regulating the organic acid metabolism.

Comparison of the Effect of Solid and Liquid Digestate on the Growth of Lettuce (Lactuca sativa L.) Plants

As a consequence of the Russian invasion of Ukraine, Europe is facing a shortage of chemical fertilizers for agriculture. Therefore, the use of byproducts of biomass anaerobic digestion, e.g., solid (SD) and liquid (LD) digestate, could be a key solution to cope with this problem. In this framework, the present study aimed to evaluate the effect of both SD and LD, derived from the same feedstock, on the biometric, physiological, and biochemical parameters of lettuce (Lactuca sativa L.) plants. Compared to the controls, the plants treated with 3% (w/w) SD showed a reduction in leaf fresh biomass, chlorophyll content, performance index, fractal dimension, and antiradical activity, while vitamin C increased by 18.8%. An opposite response was observed for the lettuce plants treated with 3% (v/w) LD, which showed an increase in all the above-mentioned parameters, except for vitamin C, which decreased by 39.8%. Interestingly, the content of malondialdehyde, which is correlated with cell membrane lipid peroxidation, increased in the SD-treated plants (+39.7%) and decreased (−42.1%) in the LD-treated plants. These results strongly support the use of LD in agriculture as a valuable product to improve the productivity and nutritional quality of crop plants.

Effect of xyloglucan-based coating enriched with cashew apple coproduct extract on quality and antioxidant metabolism of guava during ripening postharvest

This study evaluated the postharvest quality and antioxidant metabolism of ‘Paluma’ guavas treated with a xyloglucan-based coating containing an antioxidant extract from cashew apple coproduct (1%, v/v) (XCE) during ripening for 14 days at 25 °C. It was observed that XCE promoted lower levels of lipid peroxidation of cell membranes and lower activity of wall hydrolytic enzymes (polygalacturonase and pectinmethylesterase), thus a better maintenance of firmness during ripening. It was also observed that XCE increased the antioxidant potential because of the higher ascorbic acid and polyphenols content and the higher activity of antioxidant enzymes. Thus, XCE is a postharvest technology that not only improves the quality of ‘Paluma’ guavas, but also delays the oxidative ripening processes by increasing the antioxidant defense system of the fruit.

An innovative strategy to control Microcystis growth using tea polyphenols sustained-release particles: preparation, characterization, and inhibition mechanism.

Allelochemicals have been shown to inhibit cyanobacterial blooms for several years. In view of the disadvantages of "direct-added" mode, natural and pollution-free tea polyphenolic allelochemicals with good inhibitory effect on cyanobacteria were selected to prepare sustained-release particles by microcapsule technology. Results showed that the encapsulation efficiency of tea polyphenols sustained-release particles (TPSPs) was 50.6% and the particle size ranged from 700 to 970nm, which reached the nanoscale under optimum preparation condition. Physical and chemical properties of TPSPs were characterized to prove that tea polyphenols were well encapsulated and the particles had good thermal stability. The optimal dosage of TPSPs was determined to be 0.3g/L, at which the inhibition rate on Microcystis aeruginosa in logarithmic growth period could be maintained above 95%. Simultaneous decrease in algal density and chlorophyll-a content indicated that the photosynthesis of algal cells was affected leading to cell death. Significant changes of antioxidant enzyme activities suggested that Microcystis aeruginosa's antioxidant systems had been disrupted. Furthermore, TPSPs increased the concentration of O2- which led to lipid peroxidation of cell membrane and a subsequent increase in malondialdehyde (MDA) content. Meanwhile, the protein content, nucleic acid content, and electrical conductivity in culture medium rose significantly indicating the cell membrane was irreversibly damaged. This work can provide a basis for the utilization of environmentally friendly algal suppressants.

Effects of Medicinal Plants on Carbon Tetrachloride-Induced Liver Injury: A Review

The liver is the primary organ for metabolizing and eliminating foreign chemicals. When liver cells are exposed to large concentrations of dangerous substances, hepatocyte malfunction, membrane damage, and degradation may occur. Another chemical that can harm the liver is carbon tetrachloride (CCl4). CCl4 is converted into trichloromethyl radical [CCl3]- by several cytochrome P450 isoforms. [CCl3]- subsequently reacts with oxygen to generate trichloromethyl peroxyl radical [CCl3OO]- and induce lipid peroxidation in cell membranes. In this study, the mechanism by which a variety of recently identified medicinal plants display hepatoprotective activity against CCl4-induced liver injury is investigated. We find that animal models have been used in investigations of plant extracts. Herbal plants largely protect against CCl4-induced hepatotoxicity because their phytochemicals have an inhibitory nature. The antioxidant properties of phytochemicals can halt lipid oxidation and restrict the production of free radicals by inhibiting microsomal enzymes. They can also help liver cells in their fight against CCl4-induced inflammation by strengthening and fortifying them. The effectiveness of various herbs that are hepatoprotective and are thus plausible candidates for use in medicine must be confirmed. Experiments using entire plant extracts should be replaced with tests that pinpoint the active ingredients and assess the extracts’ effect on a variety of liver cell lines.

Functionalized Magnetite Nanoparticles: Characterization, Bioeffects, and Role of Reactive Oxygen Species in Unicellular and Enzymatic Systems.

The current study evaluates the role of reactive oxygen species (ROS) in bioeffects of magnetite nanoparticles (MNPs), such as bare (Fe3O4), humic acids (Fe3O4-HA), and 3-aminopropyltriethoxysilane (Fe3O4-APTES) modified MNPs. Mössbauer spectroscopy was used to identify the local surrounding for Fe atom/ions and the depth of modification for MNPs. It was found that the Fe3O4-HA MNPs contain the smallest, whereas the Fe3O4-APTES MNPs contain the largest amount of Fe2+ ions. Bioluminescent cellular and enzymatic assays were applied to monitor the toxicity and anti-(pro-)oxidant activity of MNPs. The contents of ROS were determined by a chemiluminescence luminol assay evaluating the correlations with toxicity/anti-(pro-)oxidant coefficients. Toxic effects of modified MNPs were found at higher concentrations (&gt;10-2 g/L); they were related to ROS storage in bacterial suspensions. MNPs stimulated ROS production by the bacteria in a wide concentration range (10-15-1 g/L). Under the conditions of model oxidative stress and higher concentrations of MNPs (&gt;10-4 g/L), the bacterial bioassay revealed prooxidant activity of all three MNP types, with corresponding decay of ROS content. Bioluminescence enzymatic assay did not show any sensitivity to MNPs, with negligible change in ROS content. The results clearly indicate that cell-membrane processes are responsible for the bioeffects and bacterial ROS generation, confirming the ferroptosis phenomenon based on iron-initiated cell-membrane lipid peroxidation.

Probing Lipid Peroxidation in Ferroptosis: Emphasizing the Utilization of C11-BODIPY-Based Protocols.

Ferroptosis is a form of regulated cell death that relies on iron and is characterized by the accumulation of lipid peroxides, resulting in oncotic cell swelling and eventual disruption of cellular membranes. Lipid peroxidation, a hallmark of ferroptosis, refers to the oxidative deterioration of lipids that contain carbon-carbon double bonds, particularly polyunsaturated fatty acids (PUFAs). Understanding the molecular mechanisms underlying the interplay between ferroptosis and lipid peroxidation and identifying reliable techniques for assessing lipid peroxidation levels are crucial for further advancements in this field of research. Various methods have been developed to detect lipid peroxidation levels, including C11-BODIPY (BODIPY™ 581/591 C11), liperfluo, 4-hydroxynonenal (4-HNE), malondialdehyde (MDA), Click-iT LAA (linoleamide alkyne), and liquid chromatography-mass spectrometry (LC-MS)-based epilipidomics (redox lipidomics). Currently, one of the most commonly used and effective methods is the C11-BODIPY assay, which utilizes a fluorescent probe that selectively sensitizes lipid peroxidation in cell membranes. Incorporating advanced techniques such as flow cytometry and fluorescence microscopy with C11-BODIPY dye is essential for accurate assessment of lipid peroxidation levels in ferroptosis. This chapter aims to provide comprehensive experimental protocols for detecting lipid peroxidation levels indicative of ferroptosis using C11-BODIPY staining and subsequent detection via flow cytometry and fluorescence microscopy.