Enzyme Activity Research Articles

Knockdown of LincRNACOX2 Alleviates Oxidative Stress in Pathophysiology of Acute Lung Injury

Acute lung injury (ALI) has a complicated etiology that involves oxidative stress and inflammation. The role of lncRNACox2 (lincCOX2) in ALI regulation remains unclear. In this study, the ALI model of mice and MLE-12 cell was induced by LPS. To investigate the expression of lncRNACox2 in these ALI models, we employed a nanomagnetic bead-based RNA extraction method for quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis. This enabled us to determine the levels of lncRNACox2 expression and evaluate knockdown efficiency. Moreover, we also examined lung tissue histopathology using H&E staining. Cell survival and apoptosis rates were evaluated through CCK-8 and flow cytometry, respectively. The concentration of inflammatory factors was measured using ELISA. Additionally, the concentration (8-OHdG and MDA) and enzymatic activity (CAT, GSH-Px, and SOD) of oxidative stress related factors were measured by biochemical method. The western blot was performed to present the key proteins expression level in Nrf2/ARE signaling pathway in cytoplasm and nucleoprotein. The ALI mouse model was successfully established. The histopathology change and inflammatory cells were observed by H&E staining in LPS treated groups. The expression of lincCOX2 was up-regulated in ALI tissue. LPS induced more cell death in ALI, and the knockdown of lincCOX2 improved the cell survival and suppressed the apoptosis in ALI cell. Furthermore, In addition, downregulation of lincCOX2 attenuated inflammation and oxidative stress in lung cells in ALI. The concentration of 8-OHdG and MDA were highest in the LPS group while reduced by the sh-lincCOX2, the activity of CAT, GSH-Px, and SOD was reduced in the LPS induced ALI and increased by the sh-lincCOX2. In ALI, the distribution of Nrf2 protein is transferred from cytoplasm to nucleus. Furthermore, the lincCOX2 regulated oxidative stress via Nrf2/ARE signaling pathway in ALI. Overall, downregulation of lincRNACOX2 alleviates oxidative stress in ALI via Nrf2/ARE Pathway. This study suggests that lincCOX2 may be a potential target for the treatment of ALI.

Lactiplantibacillus plantarum AR113 alleviates microbiota dysbiosis of tongue coating and cerebral ischemia/reperfusion injury in rat

Stroke is one of the leading causes of death and disability worldwide. However, information on stroke-related tongue coating microbiome (TCM) is limited, and whether TCM modulation could benefit for stroke prevention and rehabilitation is unknown. Here, TCM from stroke patients (SP) was characterized using molecular techniques. The occurrence of stroke resulted in TCM dysbiosis with significantly reduced species richness and diversity. The abundance of Prevotella, Leptotrichia, Actinomyces, Alloprevotella, Haemophilus, and TM7_[G-1] were greatly reduced, but common infection Streptococcus and Pseudomonas were remarkably increased. Furthermore, an antioxidative probiotic Lactiplantibacillus plantarum AR113 was used for TCM intervention in stroke rats with cerebral ischemia/reperfusion (I/R). AR113 partly restored I/R induced change of TCM and gut microbiota with significantly improved neurological deficit, relieved histopathologic change, increased activities of antioxidant enzymes, and decreased contents of oxidative stress biomarkers. Moreover, the gene expression of antioxidant-related proteins and apoptosis-related factors heme oxygenase-1 (HO-1), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), nuclear factor erythroid 2-related factor 2 (Nrf2), NAD(P)H:quinone oxidoreductase-1 (NQO-1), and Bcl-2 was significantly increased, but cytochrome C, cleaved caspase-3, and Bax were markedly decreased in the brain by AR113 treatment. The results suggested that AR113 could ameliorate cerebral I/R injury through antioxidation and anti-apoptosis pathways, and AR113 intervention of TCM may have the application potential for stroke prevention and control.

Redistribution of Defective Mitochondria-mediated Dihydroorotate Dehydrogenase Imparts 5-Fluorouracil Resistance in Colorectal Cancer

Although 5-fluorouracil (5-FU) is the primary chemotherapy treatment for colorectal cancer (CRC), its efficacy is limited by drug resistance. Ferroptosis activation is a promising treatment for 5-FU-resistant cancer cells; however, potential therapeutic targets remain elusive. This study investigated ferroptosis vulnerability and dihydroorotate dehydrogenase (DHODH) activity using stable, 5-FU-resistant CRC cell lines and xenograft models. Ferroptosis was characterized by measuring malondialdehyde levels, assessing lipid metabolism and peroxidation, and using mitochondrial imaging and assays. DHODH function is investigated through gene knockdown experiments, tumor behavior assays, mitochondrial import reactions, intramitochondrial localization, enzymatic activity analyses, and metabolomics assessments. Intracellular lipid accumulation and mitochondrial DHODH deficiency led to lipid peroxidation overload, weakening the defense system of 5-FU-resistant CRC cells against ferroptosis. DHODH, primarily located within the inner mitochondrial membrane, played a crucial role in driving intracellular pyrimidine biosynthesis and was redistributed to the cytosol in 5-FU-resistant CRC cells. Cytosolic DHODH, like its mitochondrial counterpart, exhibited dihydroorotate catalytic activity and participated in pyrimidine biosynthesis. This amplified intracellular pyrimidine pools, thereby impeding the efficacy of 5-FU treatment through molecular competition. These findings contribute to the understanding of 5-FU resistance mechanisms and suggest that ferroptosis and DHODH are promising therapeutic targets for patients with CRC exhibiting resistance to 5-FU.

Berberine Decreases Thrombosis Potential Induced by a High-choline Diet by Inhibiting CutC Enzyme.

Gut microbes influence thrombosis potential by generating trimethylamine N-oxide (TMAO). However, whether the antithrombotic effect of berberine is associated with TMAO generation remains unclear. The present study was designed to explore whether berberine decreases the TMAO-induced thrombosis potential and the possible mechanism underneath it. C57BL/6J female mice under a high-choline diet or standard diet were treated with/without berberine for 6 weeks. The TMAO level, carotid artery occlusion time following FeCl3 injury and platelet responsiveness were measured. The binding of berberine to the CutC enzyme was analysed with molecular docking, and molecular dynamics simulations were verified with enzyme activity assays. Results：The results showed that berberine increased the carotid artery occlusion time following FeCl3 injury and decreased the platelet hyperresponsiveness induced by a high-choline diet, both offset by intraperitoneal injection of TMAO. The effect of berberine on thrombosis potential was associated with decreasing the generation of TMAO by inhibiting the CutC enzyme. Targeting TMAO generation with berberine might be a promising therapy for ischaemic cardiac-cerebral vascular diseases.

Can plants build their niche through modulation of soil microbial activities linked with nitrogen cycling? A test with Arabidopsis thaliana.

In natural systems, different plant species have been shown to modulate specific nitrogen (N) cycling processes so as to meet their N demand, thereby potentially influencing their own niche. This phenomenon might go beyond plant interactions with symbiotic microorganisms and affect the much less explored plant interactions with free-living microorganisms involved in soil N cycling, such as nitrifiers and denitrifiers. Here, we investigated variability in the modulation of soil nitrifying and denitrifying enzyme activities (NEA and DEA, respectively), and their ratio (NEA : DEA), across 193 Arabidopsis thaliana accessions. We studied the genetic and environmental determinants of such plant-soil interactions, and effects on plant biomass production in the next generation. We found that NEA, DEA, and NEA : DEA varied c. 30-, 15- and 60-fold, respectively, among A. thaliana genotypes and were related to genes linked with stress response, flowering, and nitrate nutrition, as well as to soil parameters at the geographic origin of the analysed genotypes. Moreover, plant-mediated N cycling activities correlated with the aboveground biomass of next-generation plants in home vs away nonautoclaved soil, suggesting a transgenerational impact of soil biotic conditioning on plant performance. Altogether, these findings suggest that nutrient-based plant niche construction may be much more widespread than previously thought.

Trees adjust nutrient acquisition strategies across tropical forest secondary succession.

Nutrient limitation may constrain the ability of recovering and mature tropical forests to serve as a carbon sink. However, it is unclear to what extent trees can utilize nutrient acquisition strategies - especially root phosphatase enzymes and mycorrhizal symbioses - to overcome low nutrient availability across secondary succession. Using a large-scale, full factorial nitrogen and phosphorus fertilization experiment of 76 plots along a secondary successional gradient in lowland wet tropical forests of Panama, we tested the extent to which root phosphatase enzyme activity and mycorrhizal colonization are flexible, and if investment shifts over succession, reflective of changing nutrient limitation. We also conducted a meta-analysis to test how tropical trees adjust these strategies in response to nutrient additions and across succession. We find that tropical trees are dynamic, adjusting investment in strategies - particularly root phosphatase - in response to changing nutrient conditions through succession. These changes reflect a shift from strong nitrogen to weak phosphorus limitation over succession. Our meta-analysis findings were consistent with our field study; we found more predictable responses of root phosphatase than mycorrhizal colonization to nutrient availability. Our findings suggest that nutrient acquisition strategies respond to nutrient availability and demand in tropical forests, likely critical for alleviating nutrient limitation.

The Use of Microdosing for In vivo Phenotyping of Cytochrome P450 Enzymes: Where Do We Stand? A Narrative Review.

Cytochrome P450 (CYP) enzymes play a central role in the elimination of approximately 80% of all clinically used drugs. Differences in CYP enzyme activity between individuals can contribute to interindividual variability in exposure and, therefore, treatment outcome. In vivo CYP enzyme activity could be determined with phenotyping. Currently, (sub)therapeutic doses are used for in vivo phenotyping, which can lead to side effects. The use of microdoses (100µg) for in vivo phenotyping for CYP enzymes could overcome the limitations associated with the use of (sub)therapeutic doses of substrates. The aim of this review is to provide a critical overview of the application of microdosing for in vivo phenotyping of CYP enzymes. A literature search was performed to find drug-drug interaction studies of CYP enzyme substrates that used microdoses of the respective substrates. A substrate was deemed sensitive to changes in CYP enzyme activity when the pharmacokinetics of the substrate significantly changed during inhibition and induction of the enzyme. On the basis of the currently available evidence, the use of microdosing for in vivo phenotyping for subtypes CYP1A2, CYP2C9, CYP2D6, and CYP2E1 is not recommended. Microdosing can be used for the in vivo phenotyping of CYP2C19 and CYP3A. The recommended microdose phenotyping test for CYP2C19 is measuring the omeprazole area-under-the-concentration-time curve over 24h (AUC0-24) after administration of a single 100µg dose. CYP3A activity could be best determined with a 0.1-75µg dose of midazolam, and subsequently measuring AUC extrapolated to infinity (AUC∞) or clearance. Moreover, there are two metrics available for midazolam using a limited sampling strategy: AUC over 10h (AUC0-10) and AUC from 2 to 4h (AUC2-4).

Study of The Effect of Boswellia Leaf Extract on The Activity of Cardiac Enzymes (ALP, AST, ALT, LDH) Using Spectroscopic Methods

This study investigates the impact of Boswellia carterii leaf extracts on serum enzyme activity in myocardial infarction (MI) patients. Employing a comparative analysis between 60 healthy individuals and 40 cardiac patients, we measured the serum activity of ALP, AST, ALT, and LDH enzymes. Our findings reveal elevated enzyme activity in MI patients. We explored the inhibitory effects of aqueous, alcoholic, and ethyl acetate extracts of Boswellia carterii on these enzymes, demonstrating non-competitive inhibition. The inhibition ratio of ALT, ALP, and AST post-treatment was quantitatively assessed. Statistical analysis was conducted using SPSS-26 with independent t-tests. This research highlights the potential therapeutic role of Boswellia carterii in modulating enzyme activity associated with cardiac events, suggesting avenues for novel treatments in cardiac care.

Grafting increases superoxide dismutase and catalase activity to overcome the impact of the two-spotted spider mite on eggplant growth and productivity

Grafting vegetable crops is considered a valuable tool for improving the yield and quality of fruits under various stress conditions. This study aimed to assess the influence of grafting eggplant Solanum melongena (cv. A338) onto Solanum torvum rootstock (cv. STT3) on the incidence of the two-spotted spider mite Tetranychus urticae (TSSM). An experimental study was conducted to investigate the defense response elicited, as assessed by measuring the activities of antioxidant enzymes like superoxide dismutase (SOD) and catalase (CAT), as well as hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) and chlorophyll contents in grafted and non-grafted eggplants under different TSSM infestation levels (10, 30 and 50 adults per plant). In addition, the effect of grafting on plant growth and yield of eggplant was evaluated. According to the findings of the present study, grafted plants had a lower density of TSSM than non-grafted plants. The number of eggs, nymphs, and adults on grafted plants was 40.11%, 31.71%, and 27.54%, respectively, lower than on non-grafted plants. With increasing TSSM density, the activities of CAT and SOD were increased at varying degrees. In terms of SOD activity, the grafted plants outperformed both the non-grafted scion and rootstock at all TSSM densities. In addition, the results demonstrated that plants with greater CAT activity were able to maintain a lower H<sub>2</sub>O<sub>2</sub> content and vice versa. The lower negative impacts on photosynthetic pigments demonstrated that grafted plants on S. torvum were more resistant to mite-induced damage to chlorophyll and carotenoids as mite density elevated. The grafted plants were superior in vegetative growth, and the total fruit weight was found to be two times higher than non-grafted plants. The features modified by grafting, such as the increased activities of SOD and CAT, can alleviate the impact of TSSM. Therefore, grafting could constitute a valuable tool when combined with other strategies of Integrated Pest Management (IPM) in the two-spotted spider mite control programs.

Establishing an Artificial Pathway for the Biosynthesis of Octopamine and Synephrine.

In this study, we designed an artificial pathway composed of tyramine β-hydroxylase (TBH) and phenylethanolamine N-methyltransferase (PNMT) for the biosynthesis of both octopamine and synephrine. As most TBH and PNMT originate from eukaryotic animals and plants, the heterologous expression and identification of functional TBH and PNMT are critical for establishing the pathway in mode microorganisms like Escherichia coli. Here, three TBHs were evaluated, and only TBH from Drosophila melanogaster was successfully expressed in the soluble form in E. coli. Its expression was promoted by evaluating the effects of different expression strategies. The specific enzyme activity of TBH was optimized up to 229.50 U·g-1, and the first step in the biosynthetic pathway was successfully established and converted tyramine to synthesize 0.10 g/L of octopamine. Furthermore, the second step to produce synephrine from octopamine was developed by screening PNMT, enhancing enzyme activity, and optimizing reaction conditions, with a maximum synephrine production of 2.02 g/L. Finally, based on the optimization of the reaction conditions for each individual reaction, the one-pot cascade reaction for synthesizing synephrine from tyramine was constructed by combining the TBH and PNMT. The synthetic synephrine reached 30.05 mg/L with tyramine as substrate in the two-step enzyme cascade system. With further optimization and amplification, the titers of octopamine and synephrine were increased to 0.45 and 0.20 g/L, respectively, with tyramine as substrate. This work was the first achievement of the biosynthesis of octopamine and synephrine to date.

Regulation of Oxidative Stress and Apoptosis in Streptozotocin-Induced Diabetic Rats by Egyptian Sidr Honey.

Diabetes mellitus is a global health issue characterized by hyperglycemia which leads over time to severe damage to numerous tissues. The present study aimed to estimate the effect of Egyptian Sidr honey against streptozotocin (STZ)-induced diabetes in rats. Diabetic rats were treated with Sidr honey daily for 4 consecutive weeks. The biochemical profile of blood samples was measured. Furthermore, the activity of antioxidant enzymes, nitric oxide (NO), and malonaldehyde (MDA) were examined in hepatic and pancreatic tissues. Moreover, the expression of Bax, Caspase-3, and Bcl2 proteins were measured. Results revealed that the capability of Sidr honey to decline the elevated blood glucose and fructosamine levels. Also, the honey decreased the levels of NO and MDA. Furthermore, it regulated the antioxidant enzymes activity. Moreover, it reduced the expression levels of Caspase-3 and Bax while increased the Bcl2 level. In conclusion, Sidr honey can regulate hyperglycemia, oxidative stress, apoptosis, and antioxidant enzymes in STZ-induced diabetic rats.

Characterization of AB598, a CD39 Enzymatic Inhibitory Antibody for the Treatment of Solid Tumors.

AB598 is a CD39 inhibitory antibody being pursued for the treatment of solid tumors in combination with chemotherapy and immunotherapy. CD39 metabolizes extracellular ATP (eATP), an alarmin capable of promoting anti-tumor immune responses, into adenosine, an immuno-inhibitory metabolite. By inhibiting CD39, the consumption of eATP is reduced, resulting in a pro-inflammatory milieu in which eATP can activate myeloid cells to promote anti-tumor immunity. The preclinical characterization of AB598 provides a mechanistic rationale for combining AB598 with chemotherapy in the clinic. Chemotherapy can induce ATP release from tumor cells and, when preserved by AB598, both chemotherapy-induced eATP and exogenously added ATP promote the function of monocyte-derived dendritic cells via P2Y11 signaling. Inhibition of CD39 in the presence of ATP can promote inflammasome activation in in vitro-derived macrophages, an effect mediated by P2X7. In a MOLP8 murine xenograft model, AB598 results in full inhibition of intratumoral enzymatic activity, an increase in intratumoral ATP, a decrease of extracellular CD39 on tumor cells, and ultimately, control of tumor growth. In cynomolgus monkeys, systemically dosed AB598 results in effective enzymatic inhibition in tissues, full peripheral and tissue target engagement, and a reduction in cell surface CD39 both in tissues and in the periphery. Taken together, these data support a promising therapeutic strategy of harnessing the eATP generated by standard-of-care chemotherapies to prime the tumor microenvironment for a productive anti-tumor immune response.

Determination of soil phenanthrene degradation through a fungal-bacterial consortium.

Fungal-bacterial consortia enhance organic pollutant removal, but the underlying mechanisms are unclear. We used stable isotope probing (SIP) to explore the mechanism of bioaugmentation involved in polycyclic aromatic hydrocarbon (PAH) biodegradation in petroleum-contaminated soil by introducing the indigenous fungal strain Aspergillus sp. LJD-29 and the bacterial strain Pseudomonas XH-1. While each strain alone increased phenanthrene (PHE) degradation, the simultaneous addition of both strains showed no significant enhancement compared to treatment with XH-1 alone. Nonetheless, the assimilation effect of microorganisms on PHE was significantly enhanced. SIP revealed a role of XH-1 in PHE degradation, while the absence of LJD-29 in 13C-DNA indicated a supporting role. The correlations between fungal abundance, degradation efficiency, and soil extracellular enzyme activity indicated that LJD-29, while not directly involved in PHE assimilation, played a crucial role in the breakdown of PHE through extracellular enzymes, facilitating the assimilation of metabolites by bacteria. This observation was substantiated by the results of metabolite analysis. Furthermore, the combination of fungus and bacterium significantly influenced the diversity of PHE degraders. Taken together, this study highlighted the synergistic effects of fungi and bacteria in PAH degradation, revealed a new fungal-bacterial bioaugmentation mechanism and diversity of PAH-degrading microorganisms, and provided insights for in situ bioremediation of PAH-contaminated soil.IMPORTANCEThis study was performed to explore the mechanism of bioaugmentation by a fungal-bacterial consortium for phenanthrene (PHE) degradation in petroleum-contaminated soil. Using the indigenous fungal strain Aspergillus sp. LJD-29 and bacterial strain Pseudomonas XH-1, we performed stable isotope probing (SIP) to trace active PHE-degrading microorganisms. While inoculation of either organism alone significantly enhanced PHE degradation, the simultaneous addition of both strains revealed complex interactions. The efficiency plateaued, highlighting the nuanced microbial interactions. SIP identified XH-1 as the primary contributor to in situ PHE degradation, in contrast to the limited role of LJD-29. Correlations between fungal abundance, degradation efficiency, and extracellular enzyme activity underscored the pivotal role of LJD-29 in enzymatically facilitating PHE breakdown and enriching bacterial assimilation. Metabolite analysis validated this synergy, unveiling distinct biodegradation mechanisms. Furthermore, this fungal-bacterial alliance significantly impacted PHE-degrading microorganism diversity. These findings advance our understanding of fungal-bacterial bioaugmentation and microorganism diversity in polycyclic aromatic hydrocarbon (PAH) degradation as well as providing insights for theoretical guidance in the in situ bioremediation of PAH-contaminated soil.

Structural characterization of ligand binding and pH-specific enzymatic activity of mouse Acidic Mammalian Chitinase.

Chitin is an abundant biopolymer and pathogen-associated molecular pattern that stimulates a host innate immune response. Mammals express chitin-binding and chitin-degrading proteins to remove chitin from the body. One of these proteins, Acidic Mammalian Chitinase (AMCase), is an enzyme known for its ability to function under acidic conditions in the stomach but is also active in tissues with more neutral pHs, such as the lung. Here, we used a combination of biochemical, structural, and computational modeling approaches to examine how the mouse homolog (mAMCase) can act in both acidic and neutral environments. We measured kinetic properties of mAMCase activity across a broad pH range, quantifying its unusual dual activity optima at pH 2 and 7. We also solved high-resolution crystal structures of mAMCase in complex with oligomeric GlcNAcn, the building block of chitin, where we identified extensive conformational ligand heterogeneity. Leveraging these data, we conducted molecular dynamics simulations that suggest how a key catalytic residue could be protonated via distinct mechanisms in each of the two environmental pH ranges. These results integrate structural, biochemical, and computational approaches to deliver a more complete understanding of the catalytic mechanism governing mAMCase activity at different pH. Engineering proteins with tunable pH optima may provide new opportunities to develop improved enzyme variants, including AMCase, for therapeutic purposes in chitin degradation.

Fabrication of 3D engineered intestinal tissue producing abundant mucus by air–liquid interface culture using paper-based dual-layer scaffold

Fabrication of engineered intestinal tissues with the structures and functions as humans is crucial and promising as the tools for developing drugs and functional foods. The aim of this study is to fabricate an engineered intestinal tissue from Caco-2 cells by air–liquid interface culture using a paper-based dual-layer scaffold and analyze its structure and functions. Just by simply placing on a folded paper soaked in the medium, the electrospun gelatin microfiber mesh as the upper cell adhesion layer of the dual-layer scaffold was exposed to the air, while the lower paper layer worked to preserve and supply the cell culture medium to achieve stable culture over several weeks. Unlike the flat tissue produced using the conventional commercial cultureware, Transwell, the engineered intestinal tissue fabricated in this study formed three-dimensional villous architectures. Microvilli and tight junction structures characteristic of epithelial tissue were also formed at the apical side. Furthermore, compared to the tissue prepared by Transwell, mucus production was significantly larger, and the enzymatic activities of drug metabolism and digestion were almost equivalent. In conclusion, the air–liquid interface culture using the paper-based dual-layer scaffold developed in this study was simple but effective in fabricating the engineered intestinal tissue with superior structures and functions.

Evaluation of enzyme activity predictions for variants of unknown significance in Arylsulfatase A.

Continued advances in variant effect prediction are necessary to demonstrate the ability of machine learning methods to accurately determine the clinical impact of variants of unknown significance (VUS). Towards this goal, the ARSA Critical Assessment of Genome Interpretation (CAGI) challenge was designed to characterize progress by utilizing 219 experimentally assayed missense VUS in the Arylsulfa-tase A ( ARSA ) gene to assess the performance of community-submitted predictions of variant functional effects. The challenge involved 15 teams, and evaluated additional predictions from established and recently released models. Notably, a model developed by participants of a genetics and coding bootcamp, trained with standard machine-learning tools in Python, demonstrated superior performance among sub-missions. Furthermore, the study observed that state-of-the-art deep learning methods provided small but statistically significant improvement in predictive performance compared to less elaborate techniques. These findings underscore the utility of variant effect prediction, and the potential for models trained with modest resources to accurately classify VUS in genetic and clinical research.

Suppression of Trehalase Activity by Validamycin Induces Mortality and Developmental Delays in Sitophilus zeamais (Coleoptera: Curculionidae)

Abstract The maize weevil, Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae), is a major pest of stored grains that feeds on and develops inside the grain. The trehalose analog validamycin has a strong inhibitory effect on insect trehalase. Studies have found that validamycin affects several insects; however, no information is available on its inhibitory and physiological effects on these insects. In this study, validamycin’s inhibitory effect on trehalase was examined by incorporating it into artificial seeds and feeding them to S. zeamais. Trehalase activity was recorded throughout the developmental stages of the exposed weevils and was highest in the larval followed by adult, pupal, and egg stages. We found that feeding adult S. zeamais artificial seeds containing validamycin resulted in a significant reduction of trehalase activity in both males and females, although the primary source of trehalase was in the intestinal tract rather than in the reproductive organs. The validamycin treatment also had a concentration-dependent lethal effect, resulting in approximately 90% mortality, with females being more susceptible than males. In addition, the validamycin treatment caused a significant reduction in the number of first-generation progeny and S. zeamais demonstrated delayed development in a concentration-dependent manner. These data show that validamycin influences trehalase enzyme activity, reproductive success, and development of S. zeamais. The results obtained from this research will be valuable tools for designing a control strategy.

Inhibitory activity and molecular mechanism of the total alkaloids of Dendrobium officinale Kimura et Migo against cholesterol esterase

AbstractThis study aimed to explore the inhibitory effect and mechanism of the total alkaloids of Dendrobium officinale Kimura et Migo (DENA) against cholesterol esterase (CE). DENA was characterised by SEM, 1H NMR, and X-ray diffraction (XRD). The inhibitory effect and mechanism of DENA against CE were investigated through fluorescence chromatography, circular dichroism, and molecular docking. DENA inhibited CE activity (IC50 = 1.08 ± 0.09 mg mL−1), characterised by a non-competitive inhibition mechanism. Furthermore, DENA induced a fluorescence quenching in CE, causing a blue shift in the λmax. This coincided with a transition in the secondary structure of CE from a layered to a helical structure by circular dichroism, indicating a significant reduction in its stability. Moreover, molecular docking confirmed that DENA binds to amino acid residues in the enzyme through hydrogen bonds and hydrophobic interactions, leading to structural changes and reduced enzyme activity. These results suggest DENA has the potential to lower blood lipid levels by inhibiting CE activity.

Phytochemical Analysis, acetylcholinesterase inhibition, antidiabetic and antioxidant activity of Atriplexhalimus L. (Amaranthaceae Juss.).

Mediterranean saltbush AtriplexhalimusL. (Aranthaceae) from different bioclimatic arid zones (ten wild populations) were studied. Phenols contents, flavonoids, flavonols, tannins and anthocyanins were determined and then tested for their antioxidants, antidiabetic and anti-acetylcholinesterase (AChE)activities. Levels of total polyphenols including flavonoids and flavonols, Tannins and anthocyanins were high and varied significantly among analyzed populations.Nine phenolic acids and four flavonoids were identified for the first time in the methanolic fraction and quantified byliquid high-performance chromatography system HPLC (DAD). All extracts showed a substantial antioxidant activity, as assessed by DPPH assay (1,1-diphenyl-2-picrylhydrazyl free radical) (IC50DPPH=147.3for population of Seliena), Ferric Reducing Antioxidant Power (FRAP; IC50FRAP=3.2 for populations of Sousse and Kairouan), and Chelation Fer test (IC50FerCh=1.5 µg/mL for populations of El-hamma and Mednine).Atriplex halimuspossessed a high inhibitory effect against α-amylase activity(up to 2.6 mg ACE/gE), a moderate activity for α-glucosidase (up to 91.0 mg ACE/gE) and AChE (up to 147.2 µg/mL) compared to standard. The analyzed populations were isolated and subdivided into three distinct groups, without any bioclimatic structuration. Enzymatic activities seem to be associated with the presence, in extracts, of other classes of compounds then phenols such as terpenes,sterols, saponins, coumarins and carotenoids.

Evaluation of enzymatic antioxidant activity and reproductive hormones near and after lambing in pregnant ewes

The current study examined the levels of antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione (GSH), and Malondialdehyde (MDA) and repro ductive hormones (progesterone, estrogen, and cortisol) in pregnant local breed ewes and after lambing in the Basrah governorate. Twenty ewes were used in this study from several fields in the Basrah gov ernorate. Blood sample collection was done in three different periods, pre-lambing, immediately after lambing, and two weeks after lambing. The result showed a significant decrease (p<0.05) in SOD, CAT, and GSH-px activity before and during lambing compared to after lambing. The results also con firmed a significant increase (p<0.05) in the level of GSH pre and during lambing compared to after lambing. While evaluating, the level of MDA revealed a significant increase (p<0.05) in its level dur ing lambing compared to two weeks after lambing. Hormonal analysis showed a significant increase (p<0.05) in the levels of cortisol and estradiol pre and during lambing compared to after lambing, with a significant decrease (p<0.05) in the levels of progesterone after lambing compared to before lambing. This study concluded that during lambing, ewes were under stress factors, and an internal mechanism represented by enzymatic antioxidants like SOD, CAT, and GSH-Px acted actively during this period to neutralize the side effects of stress.