Product Of Membrane Lipid Peroxidation Research Articles

Endogenous γ-Aminobutyric Acid Accumulation Enhances Salinity Tolerance in Rice

Rice is an important food crop worldwide but is usually susceptible to saline stress. When grown on soil with excessive salt, rice plants experience osmotic, ionic, and oxidative stresses that adversely affect growth performance. γ-Aminobutyric acid (GABA) is a nonproteinogenic amino acid that plays an important role in the metabolic activities of organisms. Glutamate decarboxylase (GAD) is the rate-limiting enzyme in GABA metabolism. Here, we genetically modified rice GAD by overexpression or CRISPR-mediated genome editing. These lines, named gad3-ox1 and gad3-ox2 or gad1/3-ko, were used to explore the effects of endogenous GABA accumulation on salt tolerance in rice. Both the gad3-ox1 and gad3-ox2 lines exhibited significant accumulation of the GABA content, whereas the gad1/3-ko line presented a reduced GABA content in vivo. Notably, the two overexpression lines were markedly resistant to salt stress compared with the wild-type and knockout lines. Furthermore, our results demonstrated that endogenous GABA accumulation in the gad3-ox1 and gad3-ox2 lines increased the contents of antioxidant substances and osmotic regulators, decreased the content of membrane lipid peroxidation products and the Na+ content, and resulted in strong tolerance to salt stress. Together, these data provide a theoretical basis for cultivating rice varieties with strong salt tolerance.

Effects of two typical quinolone antibiotics in the marine environment on Skeletonema costatum

This study investigated the effects of levofloxacin (LEV) and norfloxacin (NOR) on Skeletonema costatum, focusing on cell growth, chlorophyll a (Chla) content, maximal quantum yield of PSII (Fv/Fm), protein content, enzyme activities of superoxide dismutase (SOD), glutathione reductase (GR), and glutathione peroxidase (GSH-PX), and the membrane lipid peroxidation product malondialdehyde (MDA) content were conducted to analyze the responses of S. costatum under LEV and NOR exposure. Cell growth, Chla content, Fv/Fm, protein content, enzyme activities, and MDA content were assessed to elucidate physiological changes. Both LEV and NOR inhibited S. costatum growth, except for 10 mg/L NOR, which promoted growth. Algal cells exhibited higher sensitivity to LEV, with 96h-IC50 values of 14.770 mg/L for LEV and 44.250 mg/L for NOR. Low NOR concentration (10 mg/L) increased Chla content, while high antibiotic concentrations (>20 mg/L for LEV, >100 mg/L for NOR) decreased Chla content and Fv/Fm, indicating an impact on photosynthesis. Elevated LEV and NOR levels reduced protein and MDA content but increased GR, SOD, and GSH activities, indicating induced oxidative stress. The study provides a comprehensive analysis of LEV and NOR effects on marine microalgae growth and underlying physiological mechanisms, shedding light on potential ecological risks posed by antibiotics in marine ecosystems.

The Effects of Shading on the Photosynthetic Performance of Endangered Plant Horsfieldia hainanensis Seedlings

Shading is one of the management practices for preventing the damage or injury of plant seedlings during extreme weather and climate events, such as very high temperatures and heat stress. In this study, we investigated the effects of different shading conditions on the photosynthetic characteristics of the endangered plant Horsfieldia hainanensis in Guangxi, China. The H. hainanensis seedlings in this study underwent five shading treatments, including 20% (L1), 40% (L2), 60% (L3), 80% (L4), and 100% (control) of full sunlight. The net growth of their diameter and height, and photosynthetic gas exchange parameters including their photosynthesis rate (Pn), transpiration rate (Tr), intercellular CO2 concentration (Ci), and water use efficiency (WUE) were measured for the examined seedlings. The OJIP curve and 820 nm light absorption curve, and the osmotic substances and products of membrane lipid peroxidation were employed to assess photosynthetic capacity, identify the factors constraining photosynthetic carbon assimilation, and investigate the mechanisms influencing photosystem II (PSII) and photosystem I (PSI) in the seedlings under shade stress. The results showed that the seedlings in the L2 treatments had the highest net growth and Pn, the best photosynthetic performance, and the best coordination between PSII and PSI. The net photosynthesis (Pn) levels exhibited a declining trend in the following order: L2 > L3 > L4 > L1. In the L1 treatment, non-stomatal factors emerged as the primary determinant affecting the Pn of the seedlings. The performance index (potential) of PSII, representing the conservation of absorbed photon energy to intersystem electron acceptor reduction (PIABS and ΔI/I0) of the seedlings, decreased in the order of L2 > L3 > L4 > L1. The photosystem performance and the coordination between PSII and PSI (Φ(PSI/PSII)) of the seedlings decreased in the order of L2 > L1 > L3 > L4. Under the low and moderate shading stresses (L1–L3), more serious damages occurred in PSII than in PSI, including on the donor side of PSII and in the electron transfer from QB to the acceptor side of PSI. In contrast, more considerable injury occurred in PSI than in PSII under the stress of the heavy shading treatment (L4). Considering the alterations in their leaf osmotic regulatory substances and membrane lipid peroxidation products, our findings indicate that the L2 treatment was the most conducive to the growth of the H. hainanensis seedlings. In contrast, the L1 treatment subjected H. hainanensis seedlings to the most significant stress, resulting in substantial damage to their growth and photosynthetic mechanisms. Our research provides a scientific insight into and a practical guide for the selection of an appropriate light intensity for the conservation and cultivation of endangered plant species, such as H. hainanensis.

Nitraria sibirica adapts to long-term soil water deficit by reducing photosynthesis, stimulating antioxidant systems, and accumulating osmoregulators

Amid climate change and shifts in precipitation patterns, drought conditions are expanding worldwide. Drought stress severely threatens plant growth in arid and semi-arid regions, wherein shrubs play a crucial role in maintaining ecological stability. Despite its ecological significance, studies are lacking on how Nitraria sibirica adapts to long-term drought stress. Therefore, in this study, to elucidate the mechanism of drought stress adaptation in N. sibirica, we analysed morphological, physiological, and transcriptional characteristics of plants in two soil habitats: riparian (moist) and desert (arid). The results showed that in desert soils, as soil water content decreased, leaf thickness increased, while plant height and leaf area decreased. Physiologically, photosynthesis decreased; soluble sugar, starch, proline, and hydrogen peroxide content increased significantly; while soluble proteins decreased significantly. Additionally, membrane lipid peroxidation products and antioxidant enzyme activities significantly increased under drought stress. Then, Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analysis identified 313 key genes, which were considered the most significantly enriched in the photosynthesis and photosynthetic antenna protein pathways. Further, we found that the proteins encoding photosystem II (PsbP, PsbQ, PsbR, PsbY, and Psb27), photosystem I (PsaD, PsaF, PsaG, PsaH, PsaK, and PsaO), photosynthetic electron transport (PetF), and light-trapping antenna proteins were significantly downregulated under drought stress. Taken together, these results suggest that N. sibirica adapts to long-term drought conditions by suppressing photosynthesis, activating antioxidant systems, and recruiting osmoregulators. This study provides a basis for elucidating the growth mechanisms of N. sibirica under long-term drought stress conditions.

Improving Salicornia ramosissima photochemical and biochemical resilience to extreme heatwaves through rhizosphere engineering with Plant Growth-Promoting Bacteria

The anticipated rise in the length, frequency, and intensity of heatwaves (HW) in the Mediterranean region poses a danger to the crops, as these brief but high-intensity thermal stress events halt plant productivity. This arises the need to develop new eco-friendly sustainable strategies to overcome food demand. Halophytes such as Salicornia ramosissima appear as cash crop candidates, alongside with new biofertilization approaches using Plant Growth Promoting Bacteria (PGPB). In the present work, S. ramosissima plants exposed to heatwave (HW) treatments with and without marine PGPB inoculation is studied to evaluate the physiological responses behind eventual thermal adaptation conditions. Plants exposed to HW inoculated with ACC deaminase and IAA-producing PGPB showed a 50% reduction in the photochemical energy dissipation, when compared to their non-inoculated counterparts, indicating higher light-use efficiency. The observed concomitant increase (76–234%) in several pigments indicates improved inoculated HW-exposed individuals' light harvesting and photoprotection under stressful conditions. This reduction of the physiological stress levels in inoculated plants was also evident by the significant reduction of several antioxidant enzymes as well as of membrane lipid peroxidation products. Additionally, improved membrane stability could also be observed, through the regulation of fatty acid unsaturation levels, decreasing the excessive fluidity imposed by HW treatment. All these improved physiological traits associated with specific PGP traits highlight a key potential of the use of these PGPB consortiums as biofertilizers for S. ramosissima cash crop production in the Mediterranean, where increasing frequency in HW-events is a major drawback to plant production, even to warm-climate plants.

Lipid Peroxidation Inhibitory and Cytotoxic Activities of Two Camellia Species Growing Wild in Vietnam

Background Leaves, flowers and young shoots of yellow Camellia species are often used as a substitute for green tea in Vietnam. Yellow Camellia species contain high levels of polyphenol compounds, and have shown activities such as antioxidant, anticancer, and cytotoxic. Objectives We qualitatively screened phytochemicals, quantified total polyphenols of 70% ethanol (EtOH) extracts of leaves, young shoots, and flowers of Camellia vuquangensis and Camellia hatinhensis in Ha Tinh Province, Vietnam. Furthermore, these extracts have been evaluated for lipid peroxidation inhibitory activities at the in vivo level in the BALB/c mouse model, and in vitro cytotoxic activities. Materials and Methods Chemical methods and thin-layer chromatographic (TLC) analysis were used for the qualitative screening of phytochemicals. High-performance liquid chromatography (HPLC) was used to determine total polyphenols. Cell survival was determined through optical density (OD) measured when the protein composition of the cells was stained with sulforhodamine B (SRB). Inhibition of lipid peroxidation was evaluated by determining the content of malondialdehyde (MDA), which is a product of membrane lipid peroxidation. Results The total polyphenol contents of all parts of the two species were comparable to that of green tea with values between 319.3 and 342.6 mg gallic acid equivalents (GAE/g) dry weight. Extracts of leaves, flowers of C. vuquangensis and C. hatinhensis showed strong lipid peroxidation inhibitory activities (IC50: 7.92–17.45 µg/mL) and moderate cytotoxic activities against cell lines HepG2, A549, MCF7, SK-Mel-2, HT-29, and AGS (IC50: 34.73–80.58 µg/mL). Conclusion These two tea species may be considered as herbal teas with various health benefits.

Effect mechanism of freeze–thaw cycles on browning of “Nanguo” pears peel

AbstractFreezing is an effective way to prolong the storage period of “Nanguo” pears, but the pear peel would browning during thawing. The browning mechanism of “Nanguo” pears peel under different freeze–thaw cycles was studied in this paper. The membrane lipid peroxidation products, fatty acid content and related enzyme activities of peel browning during freeze–thaw cycles were determined. The results showed that the browning of ‘Nanguo’ pears peel induced by freeze–thaw cycles might be caused by the increased of lipoxygenase (LOX) activity, the decreased of superoxide dismutase (SOD) activity and the degradation of unsaturated fatty acids. Then destroyed the integrity of cell membrane structure and resulted in the loss of cell partition, thus leading to the browning of “Nanguo” pears peel. This caused polyphenol oxidase (PPO) and peroxide (POD) to came into contact with the phenolic substrate and subsequently oxidized the phenolic to formed a brown polymer, leading to browning.Practical ApplicationsDuring the storage and transportation of frozen fruits and vegetables, freezing–thawing phenomenon occurs frequently due to temperature fluctuation, which affects their frozen quality. Freezing and thawing experiments were used to simulate the storage and transportation process to study the effect mechanism of repeated freezing and thawing on ‘Nanguo’ pears peel browning. The results provided a theoretical basis for maintaining the quality of ‘Nanguo’ pears during storage. And it is beneficial to the industrialized production of frozen pear in northeast China.

Fertility protective effect of taxifolin in cisplatin-induced ovarian damage.

The aim of our study was to investigate the protective effect of taxifolin on ovarian damage and reproductive dysfunction created by cisplatin administration. A total of 36 albino Wistar female adult rats were equally divided into 3 groups as cisplatin administered only (CIS), taxifolin+cisplatin (T+C) and healthy control group (HG). Taxifolin 50 mg/kg was administered orally by gavage in the T+C (n=12) group. In the HG (n=12) and CIS (n=12) groups, the same volume of distilled water as a solvent was orally administered. One hour after administration of taxifolin or distilled water, animals in the T+C and CIS groups were injected with cisplatin at a dose of 2.5 mg/kg intraperitoneally. This procedure was repeated once a day for 14 days. Six animals from each group were sacrificed on day 15, and their ovaries were removed for histopathological and biochemical analysis. Ovarian tissue malondialdehyde (MDA), total Glutathione (tGSH), Nuclear Factor-Kappa B (NF-kB), Tumor Necrosis Factor-α (TNF-α), Interleukin 1 beta (IL-1β), and Interleukin-6 (IL-6) levels were measured. The remaining animals (n=6 in each group) were kept in the laboratory with mature male rats for two months to breed. CIS administration led to an increase in inflammatory molecules and membrane lipid peroxidation products, and decreased the synthesis of antioxidant molecules. Compared to the CIS group, the ovarian tissue MDA, NF-kB, TNF-α, IL-1β and IL-6 levels were found to be significantly decreased in the T+C group (p<0.001 for all comparisons). On the other hand, the tGSH levels of the T+C group were significantly higher than the CIS group (p<0.001). Milder ovarian necrosis, fibrosis and follicle damage were detected in animals which were given taxifolin. Four out of the six rats (67%) treated with taxifolin gave birth within 27 days. We demonstrated, for the first time, that taxifolin ameliorates cisplatin-induced ovarian injury by decreasing MDA and proinflammatory cytokines and increasing the antioxidant enzyme. The fact that more than half of the animals receiving taxifolin became pregnant suggests that the cytoprotective effect of taxifolin is strong enough to preserve fertility.

Response mechanisms of sugarcane seedlings to the allelopathic effects of root aqueous extracts from sugarcane ratoons of different ages.

Sugarcane ratoon performance declines with increasing age due to the intergenerational accumulation and release of allelochemicals by old sugarcane roots. We aimed to clarify the effects of these allelochemicals on sugarcane seedling growth under continuous sugarcane ratoon cropping. We investigated the allelopathic effects of treatment with root aqueous extracts from sugarcane ratoons of different ages on the osmoregulatory substance content, antioxidant enzyme activity, membrane lipid peroxidation product content, photosynthetic physiological characteristics, and root exudate enzymatic characteristics of sugarcane seedlings. The root aqueous extracts exerted allelopathic effects on sugarcane seedlings. The relative electrolyte leakage, proline content, soluble protein content, soluble sugar content, malondialdehyde content, and catalase activity of the leaves were more sensitive than those of the roots. Conversely, the superoxide dismutase and peroxidase activities of the roots (positive response) were more sensitive than those of the leaves (negative response). The total chlorophyll content and net photosynthetic rate of the leaves exhibited relatively sensitive negative responses. Urease activity negatively responded but sucrase activity positively responded. We concluded that the root aqueous extracts of sugarcane ratoons may exert their allelopathic effects by affecting the level of osmoregulatory substances and causing peroxidative damage to the cell membranes of sugarcane seedlings and altering the activities of various enzymes in the rhizosphere.

High-pressure carbon dioxide treatment alleviates browning development by regulating membrane lipid metabolism in fresh-cut lettuce

The influence of high-pressure carbon dioxide (HPCD) treatment on the browning of fresh-cut lettuce was investigated during storage at 4 °C. The browning degree, color, weight loss, browning-related enzymes, and components related to membrane lipid metabolism of fresh-cut lettuce were assessed during storage. The results showed that HPCD treatment slowed down the browning of fresh-cut lettuce. Polyphenol oxidase activity and total phenolic content of HPCD-treated group were reduced by 53.50% and 74.63%, respectively. In addition, HPCD treatment inhibited lipoxygenase activity and delayed membrane lipid peroxidation, thus decreasing PAL's stimulation by membrane lipid peroxidation products and further reducing the synthesis of phenolic. On the other hand, HPCD treatment maintained the structural integrity of the cell membrane and prevented the cell membrane compartmentalization from being broken due to cell membrane breakage by inhibiting phospholipase D activity, which avoided the contact between enzyme and phenol and delayed the oxidative browning.

Exogenous Glycine Betaine Reduces Drought Damage by Mediating Osmotic Adjustment and Enhancing Antioxidant Defense in Phoebe hunanensis

Drought stress negatively impacts growth and physiological processes in plants. The foliar application of glycine betaine (GB) is an effective and low-cost approach to improve the drought tolerance of trees. This study examined the effect of exogenously applied GB on the cell membrane permeability, osmotic adjustment, and antioxidant enzyme activities of Phoebe hunanensis Hand.-Mazz under drought stress. Two levels (0 and 800 mL) of water irrigation were tested under different applied GB concentrations (0, 50, 100, and 200 mM). Drought stress decreased the relative water content by 58.5% while increased the electric conductivity, malondialdehyde, proline, soluble proteins, soluble sugars, and antioxidant enzyme activities (superoxide dismutase, catalase, peroxidase) by up to 62.9%, 42.4%, 87.0%, 19.1%, 60.5%, 68.3%, 71.7%, and 83.8%, respectively, on the 25th day. The foliar application of GB, especially at 100 mM, increased the relative water content of P. hunanensis leaves under drought stress. The concentration of GB from 50 to 100 mM effectively alleviated the improvement of cell membrane permeability and inhibited the accumulation of membrane lipid peroxidation products. Under drought stress, the concentrations of proline, soluble proteins, and soluble sugars in the leaves of P. hunanensis increased as the applied GB concentration was increased and the water stress time was prolonged. Exogenously applied GB decreased oxidative stress and improved antioxidant enzyme activities as compared with treatments without GB application. Furthermore, the physiological and biochemical indexes of P. hunanensis showed a certain dose effect on exogenous GB concentration. These results suggest that GB helps maintain the drought tolerance of P. hunanensis.

Hydrogen sulfide alleviates salinity stress in Cyclocarya paliurus by maintaining chlorophyll fluorescence and regulating nitric oxide level and antioxidant capacity

Cyclocarya paliurus is commonly used to treat diabetes in China. However, the natural habitats of C. paliurus are typically affected by salt stress. Hydrogen sulfide (H2S) is a growth regulator that is widely used to enhance plant stress tolerance, but the possible mechanism underlying H2S-alleviated salt stress in C. paliurus remains unclear. C. paliurus seedlings pretreated with NaHS (an H2S donor) were exposed to salt stress, and then, the leaf and total biomass, chlorophyll fluorescence parameters, nitric oxide (NO) content, oxidative damage, and proline and phenolic content were investigated to test the hypothesis that H2S and NO were involved in the salt tolerance of C. paliurus. The results showed that H2S pretreatment maintained chlorophyll fluorescence and attenuated the loss of plant biomass. We also found that H2S pretreatment further increased the endogenous NO content and nitrate reductase activity compared with salt treatment. Moreover, H2S pretreatment alleviated salt-induced oxidative damage, as indicated by lowered lipid peroxidation, through an enhanced antioxidant system including more proline and phenolic accumulation and increased antioxidant enzyme activities. However, C. paliurus leaves treated with the NO scavenger significantly diminished H2S-mediated NO production and alleviation of membrane lipid peroxidation. Thus, we concluded that H2S-induced NO was involved in C. paliurus salt tolerance.

The effect of cisplatin-low-level laser therapy on cell viability and death of LNCaP prostate cancer cell line.

Prostate cancer, as a common male cancer, is a serious threat to men's health. In spite of extreme developments for increasing survival rate, there are still limitations about common treatment options such as surgical procedures, radiotherapy, and chemotherapy. We hypothesized that combination of two treatments would bring better clinical outcomes. Therefore, the aim of this study was to determine the effect of conjugated cisplatin and low-level laser treatment (LLLT) on the viability of LNCaP prostate cancer cell line. LNCaP cells were harvested in DMEM containing 10% FBS and 1% antibiotic. Confluent cells were treated with different concentrations of cisplatin and different wavelengths of low-level laser (LLL) alone and in combination. The relative IC50 and cell viability was evaluated using MTT assay. Analysis of lipid peroxidation rate was performed using lipid peroxidation assay kit. LDH activity was also carried out on the treated and control cells using LDH cytotoxicity assay kit. Our results showed that combination of cisplatin and LLLT could effectively decrease cisplatin-induced cytotoxicity as well as LNCaP cell viability. Cisplatin-LLLT combination led to a significant increase in the MDA content as the product of membrane lipid peroxidation. Analyzing the LDH activity under the effect of cisplatin-LLL combined treatment showed a remarkable increase in the enzyme activity. We conclude that applying the cisplatin-LLL combination therapy is promising as an effective anti-cancer treatment. This novel combination has a potential to attenuate adverse side effects of earlier monotherapy strategies.

Effect of the Extracts of Sargassum fusiforme on Red Tide Microalgae in East China Sea

This study examined the effects of extracts of hijiki (Sargassum fusiforme) on the growth and physiology of three species of red tide microalgae (Prorocentrum donghaiensis, Skeletonema costatum, and Heterosigma akashiwo) that commonly grow in the East China Sea. The red tide algae were cultivated with the hijiki extracts at different concentrations to investigate the effects of the extracts on cells growth, chlorophyll a content, maximum quantum yield of PSII (Fv/Fm), the activities of four oxidoreductases including peroxidase (SOD), glutathione S-transferase (GST), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and the level of the membrane lipid peroxidation product, malondialdehyde (MDA). The sensitivity of red tide algae to the extracts varied among the strains, with P. donghaiensis being the most sensitive, followed by S. costatum, and then H. akashiwo. Furthermore, the extracts had a rapid lethal effect on P. donghaiensis at over 1.6 g/L and on S. costatum and P. donghaiensis at over 8 g/L. From that concentration, increasing amounts of the extracts in cultures of S. costatum promoted a reduction in Chla contents and Fv/Fm values. In addition, the oxidoreductase activity of S. costatum was reduced at 4 and 6 g/L, as shown by the reduced activity of SOD, GR, GSH-Px, GST and MDA content in the cells. The results presented herein will be useful to the development and utilization of hijiki on red tide control, and marine environmental protection.

Physiological and UPLC-MS/MS widely targeted metabolites mechanisms of alleviation of drought stress-induced soybean growth inhibition by melatonin

Long-term drought stress has irreversible effects on soybean growth and reduces yield. Melatonin can alleviate the growth inhibition and plant damage resulting from drought stress. In this study, we investigated the effects of foliar melatonin application on the physiology, metabolome growth and yield of flowering stage soybeans during drought stress. Exogenous melatonin increased the activity of antioxidant enzymes during drought stress and decreased the production of reactive oxygen species and membrane lipid peroxidation. Melatonin also mitigated lower photosynthesis ability during drought stress, and regulated carbon and nitrogen assimilation and the endogenous hormone content. A total of 518 metabolites were detected using the UPLC-MS/MS metabolome detection platform. Drought stress reduced the accumulation of sugars, amino acids, organic acid, and nucleotides, and increased the content of flavonoid and phenolic acid. Compare with drought stress treatment, melatonin reduced the content of flavonoid and phenolic acid, and increased amino acids and their derivatives (L-asparagine, L-(-)-tyrosine, L-phenylalanine, DL-homocysteine, L-methionine, 3,4-Dihydroxy, and DL-phenylalanine), flavin adenine dinucleotide (FAD), 6′-cis-cinnamoyl 8-epikingisidic acid, 5-aminocycloheptane-1,2,3-triol and 5,8,11,14-pentadecanoamide. Moreover, melatonin alleviated growth and yield declines caused by drought stress. Our study showed that exogenous melatonin improved the soybean antioxidant system and photosynthesis capacity, altering carbon and nitrogen metabolism, promoted the accumulation of amino acids and their derivatives, reducing plant growth inhibition and yield loss during drought stress. Therefore, the foliar application of melatonin has important potential in agriculture.

Phenotype, Physiology, and Gene Expression of Barley Seedlings in Response to Nano Zinc Oxide Stress

In recent years, zinc oxide nanoparticles (ZnO NPs) have been widely used as zinc fertilizers and pesticides. The use of ZnO NPs in this way can provide benefits to humans, but also has potential risks. ZnO NPs inevitably enter the environment during their production and use, which affects the ecological environment and crop growth. In order to investigate the phenotype, physiology, and gene expression of barley (Hordeum vulgare L.) seedlings under ZnO NPs stress, the barely cultivars ZJU3 (P21), Golden Promise (GP) and L23 were chosen for study. Different ZnO NPs concentrations were applied to compare the physiological and biochemical indexes of the barley seedlings and the responses of six stress-related genes, when seedlings were cultured to the two-leaf stage through hydroponics. The results showed that the density of brown spots on the leaf surface increased with increasing ZnO NPs concentration. ZnO NPs stress inhibited the root growth of barley seedlings, and P21 was the most sensitive. Furthermore, ZnO NPs stress could stimulate plants to produce a large number of reactive oxygen species (ROS), resulting in an imbalance between the production and removal of ROS and membrane lipid peroxidation in plants. This imbalance inhibited the growth and development of the barley seedlings. With increasing ZnO NPs concentration, the activity of superoxide dismutase was gradually increased, the activity of catalase was progressively decreased, and the contents of malondialdehyde and proline were increased. Compared with the control, among six stress-related genes, the expression levels of five genes were downregulated and one gene was upregulated in the experimental group. This study preliminarily revealed the toxic effect of ZnO NPs on seedlings and the effect on the expression of stress-related resistance genes in different barley varieties.

Investigation into the Effect of Photodynamic Therapy and Cisplatin on the Cervical Cancer Cell Line (A2780).

Introduction: Cervical cancer is recognized as one of the major causes of mortality among elderly women. Although there are several different therapeutic worldwide guidelines, many researchers have focused on screening new methodologies and technologies to elevate the efficiency of cervical cancer treatment. The simultaneous use of photodynamic therapy (PDT) along with chemotherapy as cisplatin has achieved good aims in the treatment of cervical cancer. Methods: A2780 cells were treated with cisplatin, photodynamic progress (laser with methylene blue as a photosensitizer compound) and a combination of cisplatin and PDT. The lithic effect of the laser, methylene blue and their combination and the IC50 value of cisplatin were calculated for each group. The amount of malondialdehyde (MDA) as membrane lipid peroxidation product and released lactate dehydrogenase was measured in the medium. The toxicity of each agent was evaluated by the MTT technique. Results: The results show that a combination of PDT and chemotherapeutic agent cisplatin caused a twofold decrease in viable cervical cancer cells compared to each therapeutic progress. The combination of both laser therapy and cisplatin enhanced cancer cell membrane disruption by increased membrane lipid peroxidation and apoptotic enzyme activation by the elevation of lactate dehydrogenase activity. Conclusion: The results indicated that cisplatin combined with PDT had a greater therapeutic effect on A2780 as a cervical cancer cell line. Therefore, PDT in combination with chemotherapy enhances the effectiveness of chemotherapeutic agents by the disruption of the cancer cell membrane and switching the apoptosis progress with less adverse effects.

Heterotrimeric G-protein \u03b1 subunit (LeGPA1) confers cold stress tolerance to processing tomato plants (Lycopersicon esculentum Mill)

BackgroundTomatoes (Lycopersicon esculentum Mill) are key foods, and their molecular biology and evolution have been well described. Tomato plants originated in the tropics and, thus, are cold sensitive.ResultsHere, we generated LeGPA1 overexpressing and RNA-interference (RNAi) transgenic tomato plants, which we then used to investigate the function of LeGPA1 in response to cold stress. Functional LeGPA1 was detected at the plasma membrane, and endogenous LeGPA1 was highly expressed in the roots and leaves. Cold treatment positively induced the expression of LeGPA1. Overexpression of LeGPA1 conferred tolerance to cold conditions and regulated the expression of genes related to the INDUCER OF CBF EXPRESSION-C-REPEAT-BINDING FACTOR (ICE-CBF) pathway in tomato plants. In the LeGPA1-overexpressing transgenic plants, the superoxide dismutase, peroxidase, and catalase activities and soluble sugar and proline contents were increased, and the production of reactive oxygen species and membrane lipid peroxidation decreased under cold stress.ConclusionsOur findings suggest that improvements in antioxidant systems can help plants cope with the oxidative damage caused by cold stress, thereby stabilizing cell membrane structures and increasing the rate of photosynthesis. The data presented here provide evidence for the key role of LeGPA1 in mediating cold signal transduction in plant cells. These findings extend our knowledge of the roles of G-proteins in plants and help to clarify the mechanisms through which growth and development are regulated in processing tomato plants.

Influence of AS-7 on the storage lesion in young and old circulating erythrocytes

Blood and its components are stored to meet the demands of blood transfusion. Erythrocytes undergo progressive modifications during storage known as storage lesions. Storage solutions were developed to improve shelf life and extend red cell viability. Therefore, the objective of this study is to analyze the effects of AS-7 on young and old erythrocytes during storage. Blood was collected from the blood bank at Kempegowda Institute of Medical Sciences (KIMS) hospital, Bengaluru. Erythrocytes were isolated from whole blood and separated based on its age using Percoll density gradient. The young and old erythrocytes were stored in AS-7 for 35 days and every 5th day, oxidative stress markers – Hemoglobin (Hb), Oxidative Hemolysis, Mechanical Fragility, Sialic Acid, Superoxides, Glucose, Lactate Dehydrogenase (LDH), Glutathione, antioxidant capacity (TACCUPRAC), Plasma Membrane Redox System (PMRS), antioxidant enzymes, lipid peroxidation, and protein oxidation products were assessed. Hb, glucose, TACCUPRAC, and superoxide dismutase reduced, while oxidative hemolysis, mechanical fragility, protein oxidation, and lipid peroxidation products increased in young and old cells over storage. LDH, PMRS, catalase, advanced oxidation protein products, and conjugate dienes were significant in old cells from day 5 itself, whereas in young cells towards the end of storage (from day 25). Oxidative insult was higher in old cells compared to young cells. AS-7 was beneficial to young erythrocytes during storage and thus laying the foundation for the possibilities of utilizing young cells as models for storage studies.

Nitrate deficiency decreased photosynthesis and oxidation-reduction processes, but increased cellular transport, lignin biosynthesis and flavonoid metabolism revealed by RNA-Seq in Oryza sativa leaves.

Rice cultivar “Weiyou916” (Oryza sativa L. ssp. Indica) were cultured with control (10 mM NO3-) and nitrate deficient solution (0 mM NO3-) for four weeks. Nitrogen (N) deficiency significantly decreased the content of N and P, dry weight (DW) of the shoots and roots, but increased the ratio of root to shoot in O. sativa. N deficiency decreased the photosynthesis rate and the maximum quantum yield of primary photochemistry (Fv/Fm), however, increased the intercellular CO2 concentration and primary fluorescence (Fo). N deficiency significantly increased the production of H2O2 and membrane lipid peroxidation revealed as increased MDA content in O. sativa leaves. N deficiency significantly increased the contents of starch, sucrose, fructose, and malate, but did not change that of glucose and total soluble protein in O. sativa leaves. The accumulated carbohydrates and H2O2 might further accelerate biosynthesis of lignin in O. sativa leaves under N limitation. A total of 1635 genes showed differential expression in response to N deficiency revealed by Illumina sequencing. Gene Ontology (GO) analysis showed that 195 DEGs were found to highly enrich in nine GO terms. Most of DEGs involved in photosynthesis, biosynthesis of ethylene and gibberellins were downregulated, whereas most of DEGs involved in cellular transport, lignin biosynthesis and flavonoid metabolism were upregulated by N deficiency in O. sativa leaves. Results of real-time quantitative PCR (RT-qPCR) further verified the RNA-Seq data. For the first time, DEGs involved oxygen-evolving complex, phosphorus response and lignin biosynthesis were identified in rice leaves. Our RNA-Seq data provided a global view of transcriptomic profile of principal processes implicated in the adaptation of N deficiency in O. sativa and shed light on the candidate direction in rice breeding for green and sustainable agriculture.