Enzyme Activity Research Articles

Вплив червоного та синього електромагнітного випромінювання на каталазну активність зародків в’юна Misgurnus fossilis L.

Photobiomodulation therapy is widely used to treat various pathological conditions. This therapy is based on the use of monochromatic light radiation. The light of the visible spectrum induces different biological effects at the molecular and cellular levels, both therapeutic and toxic. The obtained effect depends on the length of radiation, exposure, etc. One of the possible mechanisms of such influence is the regulation of pro-oxidant-antioxidant homeostasis. In order to clarify the mechanism of action of electromagnetic radiation (EMR) of different spectral composition, catalase (CAT) activity was investigated in germ cells of loach Misgurnus fossilis L. during embryogenesis. Since, loach embryos are an adequate system that reflects the physiological state of the cell both under normal conditions and as a result of the influence of various pharmacological, physical and chemical agents. The resulting zygotes were irradiated (10 min) with blue and red LEDs (λ = 460 and 660 nm, respectively). The activity of CAT was determined by the ability of hydrogen peroxi­de to form a stable colored complex with molybdenum salts. It was established that EMR of the red spectrum has the most pronounced biological effects and caused significant changes in catalase activity during embryogenesis relative to control and blue light. The maximum increase of the indicator occurs at the stage of 16 blastomeres, and at the stage of 8 and 10 divisions, a gradual decrease in enzymatic activity is observed. Irradiation by the light of the blue spectrum lasting 10 min did not cause significant changes in catalase activi­ty relative to the control at the early stages of loach embryogenesis. The obtained results suggest that CAT, one of the key enzymes of the antioxidant defense system, undergoes photoactivation under the influence of red light.

Effects of grassland degradation on soil ecological stoichiometry and soil microbial community on the South of the Greater Khingan Mountains

Grassland which covers 40% of terrestrial land is an important ecosystem having a multitude of functions, which has suffered various degrees of degradation with the interaction between global climate change and unreasonable human utilization (e.g., grazing and reclamation). Improved understanding of soil and microbial community diversity during meadow steppe degradation is crucial for predicting degradation mechanisms and restoration strategies. Here, we used Illumina sequencing technology to investigate the patterns of soil microbial community structure and the driving factors of its change across different degradation degrees of meadow steppe [i.e., non-degraded grasslands (NDG), lightly degraded grasslands (LDG), moderately degraded grasslands (MDG), and severely degraded grasslands (SDG)] south of the Greater Khingan Mountains. Our results showed a significant variation in soil properties, enzyme activity, and soil metal elements across the degraded meadows. Soil available phosphorus (AP), urease (UE), and cellulase (CL) in soils increased with the intensity of grassland degradation. Grassland degradation significantly decreased soil bacterial and fungal richness. In addition, grassland degradation significantly increased the relative abundance of Firmicutes (from 1.65% to 5.38%) and Myxococcota (from 2.13% to 3.13%). Degradation considerably increased the relative abundance of Ascomycota (from 66.54% to 75.05%), but decreased Basidiomycota (from 18.33% to 9.92%). The relative abundance of nitrogen fixation and cellulolysis decreased significantly due to grassland degradation. For fungal functional guilds, the relative abundance of pathotrophs increased while saprotrophs decreased significantly with increasing severity of degradation. Total nitrogen (TP), AP, available potassium (AK), manganese (Mn), lead (Pb), UE, sucrase (SC), and alcalase protease (ALPT) were the main drivers of soil bacterial community composition, while TP, AP, AK, Pb, UE, and SC were the main drivers of soil fungal community composition in the degraded grassland. Our findings demonstrated that severe grassland degradation has an enormous effect on soil microbial communities and soil physicochemical dynamics. These findings improve our theoretical understanding of the interactions between soil microbial populations and soil environmental variables in degraded grassland.

Effects of root-irrigation with metalaxyl-M and hymexazol on soil physical and chemical properties, enzyme activity, and the fungal diversity, community structure and function

Effects of root-irrigation with metalaxyl-M and hymexazol on soil physical and chemical properties, enzyme activity, and the fungal diversity, community structure and function

Effect of a thiazole derivative on the activity of antioxidant enzymes in murine lymphoma cells

Previous in vitro studies have demonstrated a pronounced cytotoxic effect of the thiazole derivative N-(5-Benzyl-13-thiazole-2-yl)-35-dimethyl-1-benzofuran-2-carboxami­de (BF1) on tumor cells. Additionally, it has been determined that scavengers of reactive Oxygen species (ROS) significantly reduce the cytotoxic effect of BF1. In this study, the influence of BF1 on the activity of superoxide dismutase (SOD) and catalase (CAT), both normally and in the presence of ascorbic acid, in mouse Nemeth-Kellner lymphoma (NK/Ly) cells has been studied to evaluate the possible role of antioxidant activity during the action of this substance. The experiments were performed using nonlinear male mice weighing 20–30 g. Intraperitoneal inoculation of 10–15 million cancer cells into the mice induced the ascites form of lymphoma. The thiazole derivative (BF1) was dissolved in dimethyl sulfoxide and added to the test samples at 1, 10, and 50 μM final concentrations. Superoxide dismutase (SOD) and catalase (CAT) activities were determined spectrophotometrically in a homogenate of the lymphoma cells after incubation with the drug for 30 minutes. The baseline level of SOD in the lymphoma of the mice was 0.33±0.02 activity units/min×mg protein. BF1 significantly increased the enzyme activity by 35 % and 29 % at concentrations of 10 (p<0.01) and 50 μM (p<0.05), respectively. The baseline level of CAT activity was 4.61±0.17 nmoles H2O2/min×mg protein, and this significantly decreased by 15 % (p<0.05) and 20 % (p<0.01) following the action of the thiazole derivative at a concentration of 10 and 20 μM, respectively. The increase of SOD activity, coupled with a decrease or absence of changes in CAT activity, may be cytotoxic to cancer cells. Simultaneously, upon the addition of ascorbic acid as a scavenger of ROS to the environment, the activities of SOD and CAT did not change under the action of BF1 at any of the investigated concentrations. Therefore, the effect of the thiazole derivative BF1 has been canceled in the presence of ROS scavengers in the environment. This may indicate the dependence of the cytotoxic effect of BF1 on the presence of ROS in tumor cells.

RNAseq and targeted metabolomics implicate RIC8 in regulation of energy homeostasis, amino acid compartmentation, and asexual development in Neurospora crassa

ABSTRACT Heterotrimeric G protein signaling pathways control growth and development in eukaryotes. In the multicellular fungus Neurospora crassa , the guanine nucleotide exchange factor RIC8 regulates heterotrimeric Gα subunits. In this study, we used RNAseq and liquid chromatography-mass spectrometry (LC-MS) to profile the transcriptomes and metabolomes of N. crassa wild type, the Gα subunit mutants Δ gna-1 and Δ gna-3 , and Δ ric8 strains. These strains exhibit defects in growth and asexual development (conidiation), with wild-type and Δ gna-1 mutants producing hyphae in submerged cultures, while Δ gna-3 and Δ ric8 mutants develop conidiophores, particularly in the Δ ric8 mutant. RNAseq analysis showed that the Δ gna-1 mutant possesses 159 mis-regulated genes, while Δ gna-3 and Δ ric8 strains have more than 1,000 each. Many of the mis-regulated genes are involved in energy homeostasis, conidiation, or metabolism. LC-MS revealed changes in levels of primary metabolites in the mutants, with several arginine metabolic intermediates impacted in Δ ric8 strains. The differences in metabolite levels could not be fully explained by the expression or activity of pathway enzymes. However, transcript levels for two predicted vacuolar arginine transporters were affected in Δ ric8 mutants. Analysis of arginine and ornithine levels in transporter mutants yielded support for altered compartmentation of arginine and ornithine between the cytosol and vacuole in Δ ric8 strains. Furthermore, we validated previous reports that arginine and ornithine levels are low in wild-type conidia. Our results suggest that RIC8 regulates asexual sporulation in N. crassa at least in part through altered expression of vacuolar transporter genes and the resultant mis-compartmentation of arginine and ornithine. IMPORTANCE Resistance to inhibitors of cholinesterase-8 (RIC8) is an important regulator of heterotrimeric Gα proteins in eukaryotes. In the filamentous fungus Neurospora crassa , mutants lacking ric8 undergo inappropriate asexual development (macroconidiation) during submerged growth. Our work identifies a role for RIC8 in regulating expression of transporter genes that retain arginine and ornithine in the vacuole (equivalent of the animal lysosome) and relates this function to the developmental defect. Arginine is a critical cellular metabolite, both as an amino acid for protein synthesis and as a precursor for an array of compounds, including proline, ornithine, citrulline, polyamines, creatine phosphate, and nitric oxide. These results have broad relevance to human physiology and disease, as arginine modulates immune, vascular, hormonal, and other functions in humans.

Effects of different feeding rates on growth performance, intestinal digestive enzyme activity, and intestinal microbial composition of red swamp crayfish (Procambarus clarkii)

The study aimed to investigate the effects of different feeding rates on the growth, muscle composition, intestinal digestive enzyme activities, and intestinal microbiota composition of juvenile crayfish (Procambarus clarkii). A total of 240 crayfish with an initial body weight of 8.33±0.50 g were randomly distributed into five groups, and each group had three replicates. The five groups corresponded to five different feeding rates of 2%, 4%, 6%, 8%, and 10% body weight per day (BW/day). The feeding trial lasted for six weeks. The results showed that the final body weight (FBW), weight gain rate (WGR), and specific growth rate (SGR) first increased when the feed rate increased from 2% to 6 % (P<0.05) and then showed a decreased trend with the further increase of the feeding rate, but no significant differences were observed. The feed conversion ratio (FCR) increased with a rise in feeding rate, which reached a peak at the feeding rate of 10% (P<0.05). The survival rate (SR), hepatosomatic index (HSI), and condition factor (CF) were unaffected by the feeding rates (P>0.05). The moisture, crude protein, crude fat, and ash contents of crayfish muscle remained unchanged among all feeding rate groups. Intestinal activities of lipase and amylase increase with the feeding rate (up to 6%) increasing (P<0.05). The ACE and Chao indices in the groups fed at 2% of feeding rate were significantly lower than those at a feeding rate of 10% (P<0.05). The relative abundance of Firmicutes in the groups fed at feeding rates of 4%, 6%, and 8% was higher than that in other groups (P<0.05), Citrobacter in the group fed at feeding rate of 6% was lower than that in different groups (P<0.05). The intestinal microbiota primarily functions in connection to amino acid, carbohydrate, and vitamin metabolism. Therefore, the optimum feeding rate could be 6.0% of the feeding rate of juvenile P. clarkii.

The wheat CC-NBS-LRR protein TaRGA3 confers resistance to stripe rust by suppressing Ascorbate peroxidase 6 activity

Abstract Nucleotide-binding leucine-rich repeat (NLR) proteins are intracellular immune receptors that activate innate immune responses upon sensing pathogen attack. However, the molecular mechanisms by which NLR proteins initiate downstream signal transduction pathways to counteract pathogen invasion remain poorly understood. In this study, we identified the wheat (Triticum aestivum) NLR protein Resistance Gene Analogs3 (TaRGA3), which was significantly up-regulated during Puccinia striiformis f. sp. tritici (Pst) infection. TaRGA3 and its coiled-coil (CC) domain, localized to the cytoplasm and nucleus, can induce cell death in Nicotiana benthamiana. Virus-induced gene silencing (VIGS) and overexpression suggested that TaRGA3 contributed to wheat resistance to stripe rust by facilitating reactive oxygen species (ROS) accumulation. Yeast two-hybrid, luciferase complementation imaging, and co-immunoprecipitation assays revealed that TaRGA3 interacted with wheat protein Ascorbate Peroxidase 6 (TaAPX6). Further analysis showed that TaAPX6 specifically targeted the CC domain of TaRGA3. The TaRGA3-TaAPX6 interplay led to reduced enzyme activity of TaAPX6. Notably, TaAPX6 negatively regulated wheat resistance to Pst by removing excessive ROS accompanying Pst-induced hypersensitive responses. Our findings reveal that TaRGA3 responding to Pst infection confers enhanced wheat resistance to stripe rust, possibly by suppressing TaAPX6-modulated ROS scavenging, and demonstrate that TaRGA3 can be used to engineer stripe rust resistance in wheat.

A sustainable HPTLC approach for green assessment of Tyrosine to phenylalanine ratio in chronic kidney disease

AbstractThe kidney is considered the main site for the net release of Tyrosine (Tyr) to the circulation through hydroxylation of Phenylalanine (Phe) using phenylalanine hydroxylase enzyme. In chronic kidney disease (CKD) patients the enzyme activity is impaired, therefore the serum concentration ratio of Tyr/Phe is reduced compared to healthy individuals. This motivates us to develop a cost effective, green, simple, sensitive, and selective HPTLC method to measure the levels of Tyr and Phe in serum samples. The analysis was carried out using acetonitrile: ethanol: 25% ammonia solution: ethyl acetate (6.5: 1.5: 1: 0.5) as a mobile phase. Rf values were 0.55 ± 0.05 for Phe and 0.39 ± 0.05 for Tyr. Densitometry scanning was performed using UV detector and dual wavelengths of 210 and 225 nm were obtained. A linear correlation was observed between the levels of Phe and Tyr, ranging from 50 to 700 ng band− 1 and 50 to 600 ng band− 1, respectively, under the optimum conditions. The method selectivity, linearity, precision, accuracy, and robustness were all confirmed in accordance with ICH recommendations. Calculations of the separation and resolution factors, number of theoretical plates, and height equivalent to theoretical plates prove to the chromatographic system accuracy and high separation efficiency. The developed method exhibits an acceptable eco-scale when measuring the method greenness using AGREE and GAPI softwares. It was applied for the determination of Phe and Tyr concentrations in human serum samples.

The Potential of Agaricus bisporus in Mitigating Pesticide-Induced Oxidative Stress in Honey Bees Infected with Nosema ceranae

Global climate change, environmental pollution, and frequent pesticide use severely reduce bee populations, greatly challenging beekeeping. Pesticides such as deltamethrin, a pyrethroid insecticide commonly used to control mosquitoes, can kill individual bees and entire colonies, depending on the exposure. Due to mosquito resistance to pyrethroid insecticides, components that enhance their effect are commonly used. This study explores the potential of Agaricus bisporus mushroom extract in mitigating oxidative stress in bees triggered by pesticides and Nosema ceranae infection. Our findings indicate that A. bisporus extract significantly reduced mortality rates of bees and spore counts of N. ceranae. Furthermore, the extract demonstrated antioxidant properties that lower enzyme activity related to oxidative stress (CAT, SOD, and GST) and MDA concentration, which is linked to lipid peroxidation. These results indicate that natural extracts like A. bisporus can aid bee health by mitigating the effects of pesticides and pathogens on honey bees, thus improving biodiversity.

Effect of different light conditions on the growth response of sugar beet to NaCl

ABSTRACT It is known that sugar beet, derived from a halophytic wild ancestor, is highly salt-tolerant and that moderate concentrations of NaCl enhance its growth. However, the mechanisms of this improved growth performance by NaCl are not fully understood. In this study, we investigated the effects of NaCl on sugar beet growth under different light conditions and examined the relationship between light-induced oxidative stress and the beneficial effects of NaCl. Sugar beet seedlings in pots filled with fertilized soil were grown with different light intensities (low: 150–250 μmol m−2s−1 or high: 600–1,000 μmol m−2s−1) and NaCl treatments (irrigation with water with or without 50 mM NaCl) for 10 days. The enhanced sugar beet growth by NaCl application was only observed in plants with high light intensity treatments. Moreover, high light intensity treatment increased the shoot concentration of malondialdehyde, an indicator of oxidative stress, while NaCl application decreased it. While there was a positive correlation between Na concentration and the compatible solute glycine betaine in the shoots and roots under both light intensities, a significant negative correlation between the concentrations of glycine betaine and malondialdehyde was found only in the shoots under high light intensity. Because it is known that glycine betaine activates antioxidant enzyme activities and reduces oxidative stress responses, glycine betaine synthesized in response to NaCl accumulation may have reduced the oxidative stress caused by high light intensity in the shoots, which may have caused the enhanced growth in sugar beet. Furthermore, the growth promotion by NaCl accumulation was accompanied by a significant decrease in NO3–N concentration, which suggested that NaCl application affects nitrogen metabolism in sugar beet.

Abstract A016: Targeting metabolic vulnerability of non-small cell lung cancer with annonacin and 2-deoxy-d-glucose in individual and combination modality

Abstract Non-small cell lung cancer (NSCLC) is a primary type of lung cancer and a leading cause of cancer-related mortality worldwide. The Warburg effect, characterized by increased glycolysis and reduced oxidative phosphorylation, is a hallmark of NSCLC and presents a therapeutic target. Annonacin, a natural compound found in fruits from the Annonaceae family, interferes with oxidative phosphorylation by inhibiting mitochondrial complex I. 2-deoxy-d-glucose (2DG), a glucose analog, disrupts glycolysis. This study examines the effects of Annonacin and 2DG on NSCLC A549 cells, both individually and in combination, with the hypothesis that inhibiting both metabolic pathways simultaneously will lead to more effective cancer treatment. In addition, we explored how these treatments might alter the tumor microenvironment, oxidative stress, and effects on normal epithelial bronchial cells. A549 NSCLC cells were exposed to different concentrations of Annonacin (0, 1, 2, 4, 6 µM) and 2DG (0,1.25, 2.5, 5, 10 mM), separately and together. Cell viability was measured using the MTT assay. Genotoxicity was assessed through the Comet Assay, and oxidative stress was evaluated by measuring superoxide dismutase and glutathione peroxidase activities. The long-term ability of the cells to proliferate was tested using colony-forming assays. The NL20 bronchial epithelial cell line was tested as a parallel control. Both Annonacin and 2DG showed a dose-dependent ability to kill A549 cells. However, when used together, these substances had a stronger effect, significantly lowering the number of surviving cells compared to when each was used alone. The response of this combination treatment on genotoxicity using Comet Assay is being pursued. Changes in oxidative stress responses were found, as shown by the altered superoxide dismutase and glutathione peroxidase enzyme activities. The ability of A549 cells to form colonies was greatly reduced following combination treatment, indicating a reduction in their long-term proliferative capacity. The combination of Annonacin and 2DG effectively inhibits the growth of NSCLC A549 cells by targeting their metabolic weaknesses, which may lead to increased DNA damage and oxidative stress. These results suggest simultaneous targeting glycolysis and oxidative phosphorylation could be a promising new approach for treating NSCLC. Future in vivo studies will evaluate this combination in live models and can offer insights into efficacy and possible translation to clinical application. Citation Format: Bhoj Raj Bhattarai, Cora Teets, Avinash Tope. Targeting metabolic vulnerability of non-small cell lung cancer with annonacin and 2-deoxy-d-glucose in individual and combination modality [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr A016.

α-Tocopherol Long-Chain Metabolite α-T-13'-COOH Exhibits Biphasic Effects on Cell Viability, Induces ROS-Dependent DNA Damage, and Modulates Redox Status in Murine RAW264.7 Macrophages.

The α-tocopherol long-chain metabolite α-tocopherol-13'-hydroxy-chromanol (α-T-13'-COOH) is a proposed regulatory intermediate of endogenous vitamin E metabolism. Effects of α-T-13'-COOH on cell viability and adaptive stress response are not well understood. The present study aims to investigate the concentration-dependent effects of α-T-13'-COOH on cellular redox homeostasis, genotoxicity, and cytotoxicity in murine RAW264.7 macrophages as a model system. Murine RAW264.7 macrophages are exposed to various dosages of α-T-13'-COOH to determine its regulatory effects on reactive oxygen species (ROS) production, DNA damage, expression of stress-related markers, and the activity of ROS scavenging enzymes including superoxide dismutases, catalase, and glutathione-S-transferases. The impact on cell viability is assessed by analyzing cell proliferation, cell cycle arrest, and cell apoptosis. α-T-13'-COOH influences ROS production and induces DNA damage in a dose-dependent manner. The metabolite modulates the activity of ROS-scavenging enzymes, with significant changes observed in the activities of antioxidant enzymes. A biphasic response affecting cell viability is noted: sub-micromolar doses of α-T-13'-COOH promote cell proliferation and enhance DNA synthesis, whereas supraphysiological doses lead to DNA damage and cytotoxicity. It hypothesizes an adaptive stress response, characterized by upregulation of ROS detoxification mechanisms, enhanced cell cycle arrest, and increased apoptosis, indicating a correlation with oxidative stress and subsequent cellular damage.

Precision management of Fusarium fujikuroi in rice through seed coating with an enhanced nanopesticide using a tannic acid-ZnIIformulation.

Seed coating with fungicides is a common practice in controlling seed-borne diseases, but conventional methods often result in high toxicity to plants and soil. In this study, a nanoparticle formulation was successfully developed using the metal-organic framework UiO-66 as a carrier of the fungicide ipconazole (IPC), with a tannic acid (TA)-ZnII coating serving as a protective layer. The IPC@UiO-66-TA-ZnII nanoparticles provided a controlled release, triggered and regulated by environmental factors such as pH and temperature. This formulation efficiently controlled the proliferation of Fusarium fujikuroi spores, with high penetration into both rice roots and fungal mycelia. The product exhibited high antifungal activity, achieving control efficacy rates of 84.09% to 93.10%, low biotoxicity, and promoted rice growth. Compared to the IPC flowable suspension formula, IPC@UiO-66-TA-ZnII improved the physicochemical properties and enzymatic activities in soil. Importantly, it showed potential for mitigating damage to beneficial soil bacteria. This study provides a promising approach for managing plant diseases using nanoscale fungicides in seed treatment.

Detection and functional validation of point mutations in acetylcholinesterase-1 associated with organophosphate resistance in field populations of Helicoverpa armigera.

Point mutations in the acetylcholinesterase-1 gene (ace-1) have been associated with resistance to OPs in many insects. However, the presence and function of ace-1 mutations associated with OP resistance in Helicoverpa armigera (Lepidoptera: Noctuidae), a significant lepidopteran pest damaging a wide range of crops, remain largely unexplored. This study investigated resistance to the OP insecticide phoxim in 12 field populations of H. armigera from northern China in 2022, revealing low levels of resistance (2.5- to 6.7-fold). Using an amplicon sequencing approach, we screened for ace-1 mutations in 13,874 moths collected from 114 populations collected between 2006 and 2022. We found 3 amino acid substitutions (A201S, G227E, and F290V) potentially related to OP resistance. The mean frequencies of A201S, G227E, and F290V mutations were 0.0032, 0.0001, and 0.0001, respectively. To assess these mutations' role in OP resistance, we expressed wild-type and mutant AChE1 proteins in Sf9 cells. Biochemical characterization revealed a 3.1-fold and 3.3-fold increase in the I50 of chlorpyrifos-oxon for A201S and F290V mutants compared to the wild-type enzyme, correlating with a 2.9-fold and 2.7-fold decrease in the Ki value. No enzyme activity was observed in the G227E mutant, indicating that only A201S and F290V confer insensitivity to chlorpyrifos-oxon. Our study demonstrates that amplicon sequencing is an effective method for large-scale screening of resistance-associated point mutations in field populations of H. armigera and potentially other insect pests. It also identifies A201S and F290V in AChE1 as potential point mutations conferring OP resistance in field populations of H. armigera.

Toxic effects of chlorpyrifos on biochemical composition, enzyme activity and gill surface ultrastructure of three species of small fishes from India.

The effects of chlorpyrifos, a frequently detected organophosphate in aquatic ecosystems, on biochemical (protein and glycogen) contents and oxidative enzyme activities (catalase and lipid peroxidation) in liver, muscle and gill tissues of three freshwater fish Trichogaster fasciata, Mystus vittatus and Heteropneustes fossilis were evaluated after 21-day exposure to 1 and 10% of 96h LC50 of this pesticide, which were 1.63 and 16.3µg L-1; 5.87 and 58.7µg L-1 and 2.12 and 21.2µg L-1, respectively. On comparing with control, significant reductions in protein concentration were found in liver, muscle and gill of the three fishes treated with both higher as well as lower concentrations of the pesticide except in gill of M. vittatus and liver of H. fossilis treated with the lower concentrations. Glycogen content reductions were significant in the liver and muscle of the fishes, as well as gill tissue of T. fasciata treated with the two pesticide concentrations. Significant elevations of catalase activity were found in liver of the three fishes treated with the higher concentrations, in muscle tissues of both T. fasciata and M. vittatus treated with both the concentrations and in gills of the three fishes except H. fossilis treated with the lower concentration of the pesticide. Significant elevations of lipid peroxidation level were also found in liver of all the three fish species treated with the higher concentrations, in the muscle tissue of M. vittatus as well as in the gill of T. fasciata and H. fossilis treated with both the concentrations of the pesticide. Chlorpyrifos exposed gill ultrastructure of T. fasciata, M. vittatus and H. fossilis revealed concentration-dependent effects of the pesticide on gill surface ultrastructure which include distortion of primary and secondary lamellae, deterioration of pavement cell and microridge structures, extrusion of red blood cells (RBCs), secretion of mucous layer on filament, sloughing of primary lamellae and clumping of secondary lamellae. The present study parameters could serve as useful biomarkers for evaluating the risk of pesticide toxicity to fish. These findings also point out the possible health risks to the consumers of these fish captured from contaminated water bodies.

Standard Descriptors and Selected Biomarkers in Assessment of Posidonia oceanica (L.) Delile Environmental Response

Endemic Mediterranean seagrass Posidonia oceanica is highly endangered today as it lives in a narrow infralittoral zone intensely exposed to human impact. P. oceanica beds are especially endangered in the Adriatic Sea as the central and northern Adriatic could be considered as a naturally suboptimal area for P. oceanica growth. In this research, we used some standard descriptors of Posidonia meadows at different locations and depths and determined the biochemical parameters (phenolic compounds, photosynthetic pigments, and enzyme activities) in its leaves in order to find possible correlations among the measured parameters and environmental conditions. Photosynthetic pigments were shown to be sensitive biomarkers in the assessment of P. oceanica response to different light conditions, but more research is needed to elucidate the impact of other environmental factors. Overall, the results of this research show that the studied parameters are good bioindicators of a meadow’s environmental state, but it is necessary to analyze a number of diverse indicators together to properly characterize the state of a particular P. oceanica meadow. This approach would be very useful in the determination of P. oceanica conservation status, which is the first step towards improving monitoring protocols and implementing appropriate conservation measures.

Assessment of the germination power and α-amylase activity in the soil rhizospheric compartment amended with olive mill waste waters.

Olive mill wastewater (OMWW) was used in ferti-irrigation due to its high water content, as well as its organic and mineral richness. However, this by-product also contains elevated levels of polyphenols, which may pose phytotoxic risks to soil microbiota and plants over time. To address this concern, we conducted a thorough examination of the phenolic composition of OMWW and the phenolic content of amended soils using HPLC analysis. Additionally, we assessed the residual phytotoxicity of OMWW across various soil rhizospheric layers (0-30 cm, 30-60 cm, and 60-90 cm). Standard germination tests were performed using soil extracts with sorghum (Sorghum bicolor) and tomato (Solanum lycopersicum) seeds. We also measured α-amylase activities in the germinated seeds for both species, comparing them to raw OMWW and control soil extracts. HPLC analysis revealed that tyrosol, ferulic acid, and hydroxytyrosol were the predominant phenolic compounds in crude OMWW, while no detectable compounds were found in the soil extracts. Germination tests indicated minimal toxicity in the topsoil amended with OMWW, with a noticeable reduction in residual phytotoxicity at greater depths. These results aligned with the α-amylase activity assessments, which demonstrated significantly higher enzyme activity in the deeper soil layers (30-60 cm and 60-90 cm), with no substantial differences compared to control extracts.

Genotoxic impact of agricultural insecticides as contaminants of river Teesta on the resident fish Pethia Conchonius.

Fish, being highly sensitive to changes in the physico-chemical parameters of water, are good indicators of contamination. Teesta, a prominent northern West Bengal River system, is increasingly contaminated due to anthropogenic activities. This study aims to determine agricultural pesticide contamination and its genotoxic impact on the resident fish, Pethia conchonius, as an experimental organism. Sample water analysis from three riverine sites I, II & III, showed the presence of the insecticides imidacloprid (IMI), chlorpyrifos (CPF), bifenethrin (BF), cypermethrin (CP), difenthiuron, acetamiprid (AC) in the sites II and III only with adjoining agricultural lands. Comet assay revealed a significantly lower % Head DNA (~ 1.2 times), higher %Tail DNA (~ 16 times), and %Tail length (~ 3.1 times) in the gills of Pethia conchonius from sites II and III. About 4 and 10 times increase of micronuclei and other nuclear abnormalities were also noted in the erythrocytes of the fish from sites II and III than I, which was not contaminated. The antioxidant enzymes SOD, CAT, and GST activity and MDA levels were significantly higher (p < 0.05) in the liver samples from sites II and III, while AChE activity was significantly decreased (p < 0.001) in the brain tissues. Moreover, the sod, cat, and gpx expression in the hepatic cells were significantly upregulated compared to the β actin mRNA indicating increased oxidative stress. Increased genomic damage, antioxidant enzyme activity, higher MDA levels, decreased AChE activity in the brain, and the upregulation of hepatic genes strongly suggested the genotoxic effects of the detected insecticides in combination with other contaminants.

USP1 deubiquitinates PARP1 to regulate its trapping and PARylation activity.

PARP inhibitors (PARPi) represent a game-changing treatment for patients with ovarian cancer with tumors deficient for the homologous recombination (HR) pathway treated with platinum (Pt)-based therapy. PARPi exert their cytotoxic effect by both trapping PARP1 on the damaged DNA and by restraining its enzymatic activity (PARylation). How PARP1 is recruited and trapped at the DNA damage sites and how resistance to PARPi could be overcome are still matters of investigation. Here, we described PARP1 as a substrate of the deubiquitinase USP1. At molecular level, USP1 binds PARP1 to remove its K63-linked polyubiquitination and controls PARP1 chromatin trapping and PARylation activity, regulating sensitivity to PARPi. In both Pt/PARPi-sensitive and -resistant cells, USP1/PARP1 combined blockade enhances replicative stress, DNA damage, and cell death. Our work dissected the biological interaction between USP1 and PARP1 and recommended this axis as a promising and powerful therapeutic choice for not only sensitive but also chemoresistant patients with ovarian cancer irrespective of their HR status.

The effect of silymarin on ischemia-reperfusion injury in skeletal muscles of rats silymarin and ischemia-reperfusion injury

Aim: Although the precise process is not entirely elucidated, it is well-known that oxidative stress mediators contribute to ischemia-reperfusion (I/R) injury. The impact of silymarin on I/R injury in many different tissues has been examined. For this purpose, we planned to see the effect of silymarin on muscle tissue in rats subjected to lower extremity I/R injury. Material and Methods: We used 18 male Wistar albino rats weighing 225-275 g. Each of the three groups of rats [Control (C), Ischemia-Reperfusion (I/R), and Silymarin-Ischemia/Reperfusion (S-I/R)] consisted of six rats. Silymarin was administered intraperitoneally 30 minutes before the procedure. (100 mg/kg-1) In Group I/R, the infrarenal abdominal aorta was clamped with a microvascular clamp. The clamp was removed after 120 minutes, and reperfusion was achieved for the next 120 minutes. At the end of the reperfusion period, muscle tissue samples were collected, and Malondialdehyde (MDA), catalase (CAT) enzyme activity levels and histopathological parameters were compared. Results: In the histopathological examination, no degeneration was observed in the muscle fibers in the Group C, while findings of striated muscle damage such as muscle atrophy/hypertrophy, muscle degeneration/congestion, internalization of the muscle nucleus/oval/central nucleus, fragmentation/hyalinization and leukocyte cell infiltration were seen in the Group I/R. In Group S-I/R, muscle atrophy /hypertrophy, internalization of the muscle nucleus/oval/central nucleus, fragmentation/hyalinization, and leukocyte cell infiltration were observed to improve these damaged areas compared to Group I/R. MDA levels in the Group I/R were significantly higher compared to Group C and S-I/R. The activity of the CAT enzyme was much higher in Group I/R compared to Group C. Conclusion: Our study revealed that 100 mg/kg-1 silymarin administered by intraperitoneal injection 30 minutes before ischemia effectively decreased lipid peroxidation, oxidative stress, and the injury caused by I/R in muscle histology in rats.