NO Scavenger Research Articles

Taming hemoglobin chemistry-a new hemoglobin-based oxygen carrier engineered with both decreased rates of nitric oxide scavenging and lipid oxidation.

The clinical utility of hemoglobin-based oxygen carriers (HBOC) is limited by adverse heme oxidative chemistry. A variety of tyrosine residues were inserted on the surface of the γ subunit of recombinant fetal hemoglobin to create novel electron transport pathways. This enhanced the ability of the physiological antioxidant ascorbate to reduce ferryl heme and decrease lipid peroxidation. The γL96Y mutation presented the best profile of oxidative protection unaccompanied by loss of protein stability and function. N-terminal deletions were constructed to facilitate the production of recombinant hemoglobin by fermentation and phenylalanine insertions in the heme pocket to decrease the rate of NO dioxygenation. The resultant mutant (αV1del. αL29F, γG1del. γV67F, γL96Y) significantly decreased NO scavenging and lipid peroxidation in vitro. Unlike native hemoglobin or a recombinant control (αV1del, γG1del), this mutation showed no increase in blood pressure immediately following infusion in a rat model of reperfusion injury, suggesting that it was also able to prevent NO scavenging in vivo. Infusion of the mutant also resulted in no meaningful adverse physiological effects apart from diuresis, and no increase in oxidative stress, as measured by urinary isoprostane levels. Following PEGylation via the Euro-PEG-Hb method to increase vascular retention, this novel protein construct was compared with saline in a severe rat reperfusion injury model (45% blood volume removal for 90 minutes followed by reinfusion to twice the volume of shed blood). Blood pressure and survival were followed for 4 h post-reperfusion. While there was no difference in blood pressure, the PEGylated Hb mutant significantly increased survival.

Phytochemical Profile and Antidiabetic, Antioxidant, and Anti-Inflammatory Activities of Gypsophila paniculata Ethanol Extract in Rat Streptozotocin-Induced Diabetes Mellitus.

The present study aimed to investigate the effects of the Gypsophila paniculata ethanol extract (GPEE) on oxidative stress, inflammation, and metabolic markers in a rat model of streptozotocin-induced diabetes mellitus (DM). Phytochemical analysis using high-performance liquid chromatography coupled with mass spectrometry was performed to measure the total phenolic and flavonoid contents. In vitro antioxidant activity was evaluated through DPPH, FRAP, H2O2, and NO scavenging tests, and the in vivo effects of the GPEE were assessed in streptozotocin-induced DM rats. Treatments with the GPEE, metformin, and Trolox were administrated by gavage for 10 days. On day 11, blood was collected, and serum oxidative stress (total oxidative status, oxidative stress index, malondialdehyde, advanced oxidation protein products, 8-hydroxydeoxyguanosine, nitric oxide, 3-nitrotyrosine, advanced glycation end-products, total antioxidant reactivity, total thiols), inflammatory (IL-1β, NF-κB, IL-18, and gasdermin D), metabolic (fasting glucose, total cholesterol, triglycerides, and triglyceride-glucose index), and liver injury (AST, ALT, and AST:ALT ratio) markers were measured. The GPEE was found to have a significant polyphenols content and a moderate in vitro antioxidant effect. In vivo, the GPEE lowered oxidants and increased antioxidants, decreased inflammatory markers and blood glucose, and improved lipid profiles and transaminases in a dose-dependent manner, with higher doses having a better effect, being comparable to those of metformin and Trolox.

Atmospheric pressure plasma preconditioning reduces oxygen and glucose deprivation induced human neuronal SH-SY5Y cells apoptosis by activating protective autophagy and ROS/AMPK/mTOR pathway

Reactive oxygen species (ROS)/reactive nitrogen species (RNS) exert a “double edged” effect on the occurrence and development of ischemic stroke. We previously indicate that atmospheric pressure plasma (APP) shows a neuroprotective effect in vitro based on the ROS/RNS generations. However, the mechanism is still unknown. In this work, SH-SY5Y cells were treated with oxygen and glucose deprivation (OGD) injuries for stimulating the ischemic stroke pathological injury process. A helium APP was used for SH-SY5Y cell treatment for evaluating the neuroprotective impacts of APP preconditioning against OGD injuries with the optimized parameters. During the preconditioning, APP significantly raised the extracellular and intracellular ROS/RNS production. As a result, APP preconditioning increased SH-SY5Y cell autophagy by elevating LC3-II/LC3-I ratio and autophagosome formation. Meanwhile, APP preconditioning reduced cell apoptosis caused by OGD with the increased APP treatment time, which was abolished by pretreatment with autophagy inhibitor 3-methyladenine (3-MA). The ROS scavenger N-acetyl-L-cysteine (NAC) alone or combined with NO scavenger carboxy-PTIO abolished the APP preconditioning induced SH-SY5Y autophagy and the cytoprotection, whereas the NO scavenger alone did not. In addition, we observed the elevated phosphorylation of AMP-activated protein kinase (AMPK) and decreased phosphorylation of mammalian target of rapamycin (mTOR) in APP treated SH-SY5Y cells. This effect was attenuated by AMPK inhibitor Compound C (CC), the ROS scavenger NAC and autophagy inhibitor 3-MA. Furthermore, the cytoprotective effect of APP was preliminarily confirmed in the rats of middle cerebral artery occlusion (MCAO) model. Results showed that APP inhalation by rats during MCAO process could improve neurological functions, reduce cell apoptosis in brain tissues and decrease cerebral infarct volume. Our data suggested that ROS produced by APP preconditioning played a vital role in the neuroprotective effect of SH-SY5Y cells against OGD injuries by activating autophagy and ROS/AMPK/mTOR pathway.

Optimization of the Search for Neuroprotectors among Bioflavonoids.

For the first time, to optimize the creation of new neuroprotective agents based on bioflavonoids, we applied information technologies; these include docking analysis to calculate the binding of candidate molecules to the pharmacological target protein transthyretin as well as a program of virtual screening of NO scavengers. As a result of this approach, the substance catechin was isolated from candidate molecules-quercetin, catechin, Epicatechin gallate, Epicatechin, Procyanidin B1, Procyanidin B2, Procyanidin B3, and Catechin-3-gallate-according to docking analysis. As a result of virtual screening, catechin was identified as a potential NO scavenger (55.15% prediction). The results of the prediction were confirmed by in vitro experiments. Course administration of catechin to animals with experimental multiple sclerosis (MS) against the background of methylprednisolone administration completely eliminated lethal cases, reduced the number of diseased animals by 20% as well as prevented the development of severe neurological symptoms by 20% (compared to the methylprednisolone group) and by 60% compared to the control group. Course administration of catechin with methylprednisolone leads to a decrease in the neurodegradation markers in the cytosol of rats, with EAE: NSE by 37% and S-100 by 54.8%. The combined administration of methylprednisolone significantly exceeds the combination of methylprednisolone with the reference drug mexidol by the degree of NSE reduction. The obtained results indicate a significant neuroprotective effect of ocular combinations of methylprednisolone and catechin. The above-mentioned confirms the correctness of the bioflavonoid selection with the help of a virtual screening program.

HPLC phytochemical profiling, antioxidant activity and in vitro evaluation of inhibitory effects of Terminalia catappa stem bark extract on enzymes linked to diabetes, hypertensive vasoconstriction and erectile dysfunction

BackgroundTerminalia catappa is a traditional medicinal plant used for several ailments among the local folks. Among the locals, the stem bark is an important constituent of polyherbal remedies for the treatment of cancer and metabolic diseases; however, there is a paucity of scientific reports on it. This study aimed to evaluate the in vitro antidiabetic, antihypertensive and antierectile dysfunction effects of Terminalia catappa stem bark extract (TSBE). MethodsThe HPLC phytochemical profiling, total phenol content, total flavonoid content and antioxidant capacity of the extract were delineated. The inhibitory effects of TSBE on activities of α-glucosidase, α-amylase, acetylcholinesterase (AChE), arginase, phosphodiesterase-5′ (PDE-5′), angiotensin-converting enzyme (ACE) and ecto-5 nucleotidase (Ecto-5-NTD) were estimated following standard procedures. ResultsHPLC of TSBE profiled ferulic acid, gallic acid, caffeic acid, catechin, rutin, p-coumaric acid, chlorogenic acid, kaempferol, apiginin and quercetin. TSBE had IC50 values of 49.19 µg/mL and 55.42 µg/mL in terms of scavenging DPPH and NO radicals, respectively. The TSBE inhibited α-glucosidase and α-amylase activities with IC50 values of 71.53 µg/mL and 105.11 µg/mL, respectively. The inhibitory effects of TSBE on AChE, arginase, PDE-5′, and ACE revealed IC50 values higher than that of standards. TSBE demonstrated a stimulatory effect on ecto-5-NTD activity. ConclusionTSBE revealed promising antioxidant, antidiabetic, antihypertensive and antierectile dysfunction (anti-ED) properties which may be associated with the bioactive compounds present in the extract.

Products of oxidative and non-oxidative metabolism of L-arginine as potential regulators of Ca2+ transport in mitochondria of uterine smooth muscle

Mitochondria play a crucial role in maintaining Ca2+ homeostasis in cells. Due to the critical regulatory role of the products of oxidative and non-oxidative metabolism of L-arginine, it is essential to clarify their effect on Ca2+ transport in smooth muscle mitochondria.Experiments were performed on the uterine myocytes of rats and isolated mitochondria. The possibility of NO synthesis by mitochondria was demonstrated by confocal microscopy and spectrofluorimetry methods using the NO-sensitive fluorescent probe DAF-FM and Mitotracker Orange CM-H2TMRos. It was shown that 50 μM L-arginine stimulates the energy-dependent accumulation of Ca2+ in mitochondria using the fluorescent probe Fluo-4 AM. A similar effect occurred when using nitric oxide donors 100 μM SNP, SNAP, and sodium nitrite (SN) directly. The stimulating effect was eliminated in the presence of the NO scavenger C-PTIO. Nitric oxide reduces the electrical potential in mitochondria without causing them to swell. The stimulatory effect of spermine on the accumulation of Ca2+ by mitochondria is attributed to the enhancement of NO synthesis, which was demonstrated with the use of C-PTIO, NO-synthase inhibitors (100 μM NA and L-NAME), as well as by direct monitoring of NO synthesis fluorescent probe DAF-FM.A conclusion was drawn about the potential regulatory effect of the product of the oxidative metabolism of L-arginine – NO on the transport of Ca2+ in the mitochondria of the myometrium, as well as the corresponding effect of the product of non-oxidative metabolism –spermine by increasing the synthesis of NO in these subcellular structures.

A facile bio–inspired route of synthesizing Solanum sisymbriifolium fruit extract mediated silver nanoparticles: Pharmaceutical and environmental aspects

The present research work focused on biological synthesis of silver nanoparticles using Solanum sisymbriifolium aqueous fruit extract (AgNPs@SsFE) and determining their pharmaceutical and environmental aspects for the first time. The phytochemicals extracted from S. sisymbriifolium fruit extract (SsFE) contributed in reducing the average particle size of green synthesized AgNPs@SsFE to 23.17 nm and served as capping agents. Further, when AgNPs@SsFE were characterized using PSA, ZP, FE–SEM, Elemental mapping, EDX, HR–TEM, SAED, FTIR and XRD, exhibited the high colloidal stability, spherical shape and crystalline nature of the nanoparticles. Moreover, the synthesized AgNPs@SsFE exhibited enhanced antioxidant activity in comparison to SsFE when assayed via DPPH, FRAP, •NO and H2O2 scavenging methods. The Agar well–diffusion analysis unveiled AgNPs@SsFE to possess greater antibacterial activity against highly pathogenic gram–negative strains than gram–positive strains. Besides, the synthesized AgNPs@SsFE established itself to be a strong photocatalyst by degrading the methylene blue cationic dye under Solar and UV irradiations. These features of synthesized AgNPs@SsFE are found promising to convince the efficacy of SsFE in synthesizing the nanoparticles which can be useful in modern medicine and clinical applications.

Aortic Valve Stenosis Causes Accumulation of Extracellular Hemoglobin and Systemic Endothelial Dysfunction.

Whether aortic valve stenosis (AS) can adversely affect systemic endothelial function independently of standard modifiable cardiovascular risk factors is unknown. We therefore investigated endothelial and cardiac function in an experimental model of AS mice devoid of standard modifiable cardiovascular risk factors and human cohorts with AS scheduled for transcatheter aortic valve replacement. Endothelial function was determined by flow-mediated dilation using ultrasound. Extracellular hemoglobin (eHb) concentrations and nitric oxide (NO) consumption were determined in blood plasma of mice and humans by ELISA and chemiluminescence. This was complemented by measurements of aortic blood flow using 4-dimensional flow acquisition by magnetic resonance imaging and computational fluid dynamics simulations. The effects of plasma and red blood cell (RBC) suspensions on vascular function were determined in transfer experiments in a murine vasorelaxation bioassay system. In mice, the induction of AS caused systemic endothelial dysfunction. In the presence of normal systolic left ventricular function and mild hypertrophy, the increase in the transvalvular gradient was associated with elevated eryptosis, increased eHb, and increased plasma NO consumption; eHb sequestration by haptoglobin restored endothelial function. Because the aortic valve orifice area in patients with AS decreased, postvalvular mechanical stress in the central ascending aorta increased. This was associated with elevated eHb, circulating RBC-derived microvesicles, eryptotic cells, lower haptoglobin levels without clinically relevant anemia, and consecutive endothelial dysfunction. Transfer experiments demonstrated that reduction of eHb by treatment with haptoglobin or elimination of fluid dynamic stress by transcatheter aortic valve replacement restored endothelial function. In patients with AS and subclinical RBC fragmentation, the remaining circulating RBCs before and after transcatheter aortic valve replacement exhibited intact membrane function, deformability, and resistance to osmotic and hypoxic stress. AS increases postvalvular swirling blood flow in the central ascending aorta, triggering RBC fragmentation with the accumulation of hemoglobin in the plasma. This increases NO consumption in blood, thereby limiting vascular NO bioavailability. Thus, AS itself promotes systemic endothelial dysfunction independent of other established risk factors. Transcatheter aortic valve replacement is capable of limiting NO scavenging and rescuing endothelial function by realigning postvalvular blood flow to near physiological patterns. URL: https://www.clinicaltrials.gov; Unique identifiers: NCT05603520 and NCT01805739.

Mushrooms grown in high-altitude soil exhibiting distinct alterations in growth, biochemical composition and antioxidant potential

Functional foods like mushrooms are high in secondary metabolites and bioactive chemicals with anti-inflammatory, antibacterial, antidiabetic, immune-stimulating and other health-promoting qualities. This study investigates four mushroom varieties including Cordyceps militaris, Pleurotus ostreatus, Pleurotus djamor and Agaricus bisporus, grown on Indian soil and natural environment for measurement of phenol and flavonoid content, along with their antioxidant properties and biochemical makeup. They had a large amount of phenolic and flavonoid content and high DPPH, H2O2 and NO scavenging inhibition percentages, demonstrating strong antioxidant potential. These mushroom extracts also contained a sizable amount of proline and nutritional content like carbohydrate, protein, lipids and fiber. Among all the mushrooms, the biochemical profile was significantly highest. Significant variations were also seen in the amounts of moisture and ash in each sample. This research aimed to determine how mixing soil with compost substrate affected the yield and growth of mushrooms. The soil had a massive impact on forming more mycelial colonies which were necessary for the entire spawn run and spawning to pin head production and for the maturation of pins. It was discovered through this research that combining soil and compost substrate can aid in the growth of good-quality mushrooms and improve their productivity.

Synthesis, molecular docking studies and biological evaluation of N-(4-oxo-2-(trifluoromethyl)-4H-chromen-7-yl) benzamides as potential antioxidant, and anticancer agents

A series of novel chromone derivatives of (N-(4-oxo-2-(trifluoromethyl)-4H-chromen-6-yl) benzamides) were synthesized by treating 7-amino-2-(trifluoromethyl)-4H-chromen-4-one with K2CO3 and/or NaH, suitable alkyl halides and acetonitrile and/or 1,4-dioxane. The obtained products are in high yields (87 to 96%) with various substituents in short reaction times with no more by-products and confirmed by FT-IR, 1H, and 13C-NMR Spectral data. The in vitro cytotoxic activity was examined against two human cancer cell lines, namely the human lung adenocarcinoma (A-549) and the human breast (MCF-7) cancer cell line. Compound 4h showed promising cytotoxicity against both cell lines with IC50 values of 22.09 and 6.40 ± 0.26 µg/mL respectively, compared to that of the standard drug. We also performed the in vitro antioxidant activity by DPPH radical, hydrogen peroxide, NO scavenging, and total antioxidant capacity (TAC) assay methods, and they showed significant activities. The possible binding interactions of all the synthesized chromone derivatives are also investigated against selective pharmacological targets of human beings, such as HERA protein for cytotoxic activity and Peroxiredoxins (3MNG) for antioxidant activity which showed closer binding free energies than the standard drugs and evidencing the above two types of activities.

Organosulfur Compounds in Aged Garlic Extract Ameliorate Glucose Induced Diabetic Cardiomyopathy by Attenuating Oxidative Stress, Cardiac Fibrosis, and Cardiac Apoptosis.

Diabetic cardiomyopathy has emerged as a major cause of cardiac fibrosis, hypertrophy, diastolic dysfunction, and heart failure due to uncontrolled glucose metabolism in patients with diabetes mellitus. However, there is still no consensus on the optimal treatment to prevent or treat the cardiac burden associated with diabetes, which urges the development of dual antidiabetic and cardioprotective cardiac therapy based on natural products. This study investigates the cardiotoxic profile of glucose and the efficacy of AGE against glucose-induced cardiotoxicity in H9c2 cardiomyocytes. The cellular metabolic activity of H9c2 cardiomyocytes under increasing glucose concentration and the therapeutic efficacy of AGE were investigated using the MTT cell cytotoxicity assay. The in vitro model was established in six groups known as 1. control, 2. cells treated with 25 µM glucose, 3. 100 µM glucose, 4. 25 µM glucose +35 µM AGE, 5. 100 µM glucose + 35 µM AGE, and 6. 35 µM AGE. Morphological and nuclear analyses were performed using Giemsa, HE, DAPI, and PI, respectively, whereas cell death was simultaneously assessed using the trypan blue assay. The antioxidant potential of AGE was evaluated by DCFH-DA assay, NO, and H202 scavenging assay. The activities of the antioxidant enzymes catalase and superoxide dismutase were also investigated. The antiglycative potential of AGE was examined by antiglycation assays, amylase zymography, and SDS PAGE. These results were then validated by in silico molecular docking and qRTPCR. Hyperglycemia significantly reduced cellular metabolic activity of H9c2 cardiomyocytes, and AGE was found to preserve cell viability approximately 2-fold by attenuating oxidative, fibrosis, and apoptotic signaling molecules. In silico and qRTPCR studies confirmed that organosulfur compounds target TNF-α, MAPK, TGF-β, MMP-7, and caspase-9 signaling molecules to ameliorate glucose-induced cardiotoxicity. AGE was found to be an antidiabetic and cardioprotective natural product with exceptional therapeutic potential for use as a novel herb-drug therapy in the treatment of diabetic cardiomyopathy in future therapies.

Gadolinium-Based Magnetic Resonance Theranostic Agent with Gallic Acid as an Anti-Neuroinflammatory and Antioxidant Agent.

Studies in the field have actively pursued the incorporation of diverse biological functionalities into gadolinium-based contrast agents, aiming at the amalgamation of MRI imaging and therapeutic capabilities. In this research, we present the development of Gd-Ga, an anti-neuroinflammatory MR contrast agent strategically designed to target inflammatory mediators for comprehensive imaging diagnosis and targeted lesion treatment. Gd-Ga is a gadolinium complex composed of 1,4,7-tris(carboxymethylaza)cyclododecane-10-azaacetylamide (DO3A) conjugated with gallic acid (3,4,5-trihydroxybenzoic acid). Upon intravenous administration in LPS-induced mouse models, Gd-Ga demonstrated a remarkable three-fold increase in signal-to-noise (SNR) variation compared to Gd-DOTA, particularly evident in both the cortex and hippocampus 30 min post-MR monitoring. In-depth investigations, both in vitro and in vivo, into the anti-neuroinflammatory properties of Gd-Ga revealed significantly reduced protein expression levels of pro-inflammatory mediators compared to the LPS group. The alignment between in silico predictions and phantom studies indicates that Gd-Ga acts as an anti-neuroinflammatory agent by directly binding to MD2. Additionally, the robust antioxidant activity of Gd-Ga was confirmed by its effective scavenging of NO and ROS. Our collective findings emphasize the immense potential of this theranostic complex, where a polyphenol serves as an anti-inflammatory drug, presenting an exceptionally efficient platform for the diagnosis and treatment of neuroinflammation.

Synthesis and Therapeutic Potential of selected Schiff Bases: In vitro Antibacterial, Antioxidant, Antidiabetic, and Computational Studies

AbstractIn this study, three Schiff base compounds, (E)‐N‐(4‐bromophenyl)‐1‐(2‐nitrophenyl)methanimine (L1), (E)‐2‐((mesitylimino)methyl)phenol (L2), and (E)‐N‐(4‐bromophenyl)‐1‐(pyridin‐2‐yl)methanimine (L3), were synthesized and characterized by various spectroscopic techniques. The antibacterial activity of the compounds was evaluated against Gram‐positive and Gram‐negative bacteria, with L3 demonstrating the most significant activity. The compounds were also evaluated for their antioxidant activity using DPPH, FRAP, and NO scavenging assays. While the compounds exhibited concentration‐dependent scavenging of free radicals, their activity was not as significant as that of the reference, Trolox. Furthermore, L1–L3 were tested for their α‐amylase and α‐glucosidase inhibitory activity, with L1 showing the highest inhibitory activity among the three compounds. The DFT study showed that L1 is the most chemically reactive among the three compounds, having the lowest energy band gap value of 3.82 eV in acetonitrile, the experimental solvent. Molecular docking predicted that L1 and L2 have very strong inhibition equivalents to the standard drugs against bacteria and diabetes. All the compounds showed stronger inhibition against α‐glucosidase than acarbose, while only L1 and L2 exhibited stronger inhibition against α‐amylase than acarbose. It can be deduced that the theoretical studies corroborate well with the experimental, and compounds with the electron‐withdrawing group displayed better medicinal properties than their electron‐donating counterparts.

Anti-Shigella and antioxidant-based screening of some Cameroonian medicinal plants, UHPLC-LIT-MS/MS fingerprints, and prediction of pharmacokinetic and drug-likeness properties of identified chemicals.

Ethnopharmacological relevanceShigella infection is a public health problem responsible for approximately 700,000 deaths annually. The management of this disease is impaired by the emergence of multidrug-resistant Shigella species, highlighting the urgent need to search for alternative treatment options. In this regard, investigating medicinal plants traditionally used for the treatment of dysentery, diarrheal infections, and/or associated symptoms in endemic regions might provide an opportunity to identify phytochemicals that could be further used as a basis for the development of future anti-shigella drug candidates. Aim of the studyThis study was designed to investigate the anti-shigella and antioxidant-based ethnopharmacological potency of some Cameroonian medicinal plants with an emphasis on pharmacokinetic properties of the identified chemical pharmacophore. Materials and methodsBriefly, plant species were selected and collected based on their ethnopharmacological uses and information reported in the literature. Crude aqueous, ethanolic, methanolic, and hydroethanolic (30:70, v/v) extracts from these plants were prepared and then screened for their anti-Shigella activity against four Shigella strains and cytotoxicity against Vero and Raw cell lines using microdilution and resazurin-based methods, respectively. The antioxidant activities of potent extracts were evaluated using DPPH, ABTS, NO, and FRAP scavenging assays. The chemical profile of potent extracts was performed using the UHPLC-LIT-MS/MS and the pharmacokinetic properties, druglikeness, and likely molecular targets of the chemical scaffolds identified were predicted using SwissADME and SwissTargetPredictor. ResultsThirty-nine (39) plants belonging to 26 plant families were harvested. Out of the 228 extracts tested, 18 extracts originating from 6 plants (15.38 %) were active (MICs 250–1000 μg/mL) and nontoxic toward Vero (CC50 129.25–684.55 μg/mL) and Raw cell lines (CC50 336.20 to >1000 μg/mL). Six potent extracts from the two plants exhibited moderate to potent DPPH (SC50 8.870–54.410 μg/mL), ABTS (SC50 12.020–27.36 μg/mL), and NO (SC50 0.02–195.85 μg/mL) scavenging activities. Later, these extracts showed interesting ferric iron-reducing power (1.28–12.14 μg equivalent NH2OH/g of extract). The shortest onset of action time (4 and 6 h) observed following inhibition kinetics studies was observed with extracts BFSHE, PMSE, and PMSM. The UHPLC-LIT-MS/MS and some databases (Mass Spectral Library (NIST 14), Human Metabolome Database (HMD), MassBank, SuperNatural 3.0, The Food Database (FooDB), and Chemical Entities of Biological Interest (ChEBI)) allowed the annotation of 18 and 17 metabolites in the extracts from stem bark of P. macrophylla and B. ferruginea respectively. Pharmacokinetic prediction of these chemicals showed that compound 6 (4,6a-bis(Hydroxymethyl)-9a-methyl-3-oxo-1a,1b,3,5,6,6a,7a,9a-octahydrobis (oxireno)[2′,3':5,6; 2″,3'':9,10]cyclodeca[1,2-b]furan-5-yl methacrylate), compound 8 (Corynoxeine), and compounds 35 (Stachybotrydial acetate) demonstrated acceptable druglike and pharmacokinetic properties and might act through inhibition of kinase, transferase, protease, oxidoreductase, and family AG protein-linked receptors. ConclusionThe findings from this investigation demonstrated that Cameroonian medicinal plants are suitable reservoirs of anti-Shigella and antioxidant agents with good drug candidate properties.

Regulation of a novel DsGATA1 from Dunaliella salina on the synthesis of carotenoids under red light.

Dunaliella salina is a high-quality industrial effector for carotenoid production. The mechanism by which red light regulates carotenoid synthesis is still unclear. In this study, a transcription factor of DsGATA1 with a distinct structure was discovered in D. salina. The recognition motif of DsGATA1 was comparable to that of plant and fungal GATA, despite its evolutionary proximity to animal-derived GATA. The expression of DsGATA1 in D. salina was still noticeably decreased when exposed to red light. Analysis of physiological and biochemical transcriptomic data from overexpressed, interfering, and wild-type strains of DsGATA1 revealed that DsGATA1 acts as a global regulator of D. salina carotenoid synthesis. The upregulated genes in the CBP pathway by DsGATA1 were involved in its regulation of the synthesis of carotenoids. DsGATA1 also enhanced carotenoid accumulation under red light by affecting N metabolism. DsGATA1 was found to directly bind to the promoter of nitrate reductase to activate its expression, promoting D. salina nitrate uptake and accelerating biomass accumulation. DsGATA1 affected the expression of the genes encoding GOGAT, GDH, and ammonia transporter proteins. Moreover, our study revealed that the regulation of N metabolism by DsGATA1 led to the production of NO molecules that inhibited carotenoid synthesis. However, DsGATA1 significantly enhanced carotenoid synthesis by NO scavenger removal of NO. The D. salina carotenoid accumulation under red light was elevated by 46% in the presence of overexpression of DsGATA1 and NO scavenger. Nevertheless, our results indicated that DsGATA1 could be an important target for engineering carotenoid production. KEY POINTS: • DsGATA1 with a distinct structure and recognition motif was found in D. salina • DsGATA1 enhanced carotenoid production and biomass in D. salina under red light • DsGATA1 is involved in the regulation of N metabolism and carotenoid synthesis.

Hydroalcoholic extract: A potential source from Azadirachta indica a Juss flower for DNA and BSA binding, scavenging, fungicidal, and larvicidal activities

AbstractThe present study focuses on the evaluation of the DNA and BSA binding capability, anti‐fungal, metal chelation, and larvicidal activity of extracts of Azadirachta indica A Juss flower. The different extracts of A. indica was prepared by soxhlet extraction using Petroleum Ether (PE), acetone (AC), and hydroalcohol (HA) as solvents. DNA and BSA binding ability of HA extract was calculated through the UV–Visible titrimetric method. The phytochemicals present in the extract show good binding ability towards DNA and BSA. H2O2 and NO scavenging activity were evaluated and HA extracts shows good antioxidant activity with IC50 values of 62 and 48 μg/mg, respectively. The metal chelating property was calculated, where HA shows good chelating ability with the IC50 value of 32.23 μg/mg. The antifungal activity of these extracts was evaluated against different fungal stains; among them, hydroalcoholic extract shows a higher zone of inhibition in all the fungal stains than Petroleum Ether and acetone extracts and acetone extracts (i.e., 50 μg/μL MIC). The potential extract (i.e., HA extract) was used to estimate the larvicidal activity of parasites. The % of mortality was evaluated through a dose‐dependent assay and it is confirmed that when concentration increases, the mortality rate increases. The correlation between metal chelating activity and total flavonoid and phenolic content was calculated and it was found that there is a good correlation (R2 – .743 and .902, respectively). These results proved that HA extract possesses biologically important phytochemicals that contribute to pharmaceutical and biological activities and could be a natural remedy for various real‐time applications.

Nyctanthes arbortristis: In Vitro Efficacy Of Anti-Oxidant Potential And Cytotoxicity Study Of Bark Extracts On Sw982 Rheumatoid Arthritis Cell Line Followed By Phytochemical Profiling By GCMS

Nyctanthes arbortristis, commonly known as the night-jasmine, is a plant rich in bioactive compounds with potential therapeutic benefits. This study aimed to evaluate the antioxidant properties and cytotoxic effects of Nyctanthes arbortristis bark extracts on SW982 rheumatoid arthritis cell line in vitro. Sequential solvent extraction method was employed to obtain extracts with varying polarities. The antioxidant potential of the extracts was assessed using DPPH, ABTS, NO, and H2O2 radical scavenging assays and total phenolic and flavonoid content determination. Cytotoxicity was evaluated using MTT assay on SW982 cells. Results revealed that the bark extracts exhibited significant antioxidant activity, with the methanol extract showing the highest radical scavenging activity, total phenolic content and total flavonoids contents. Furthermore, the bark extracts demonstrated concentration-dependent cytotoxic effects on SW982 cells, with the ethyl acetate extract exhibiting the most potent cytotoxicity. These findings suggest that Nyctanthes arbortristis bark extracts possess substantial antioxidant potential and cytotoxic effects against SW982 rheumatoid arthritis cells, indicating their potential as therapeutic agents in the management of rheumatoid arthritis. Further investigations are warranted to elucidate the underlying mechanisms and evaluate their efficacy in vivo.

Effects of black seed oil combined with olive oil or honey on antioxidant activities, phenolic content, and identification and quantification of thymoquinone, a key bioactive compound

The plant Nigella sativa (NS) has a rich history in folk medicine, being utilized for various illnesses and as tonic drugs. Furthermore, thymoquinone (TQ), a major compound found in the seeds of NS, may exhibit antioxidant activity. In addition to black candles, traditional medicine employs olive oil and honey to nourish the body. Some folk medicine systems combine NS, honey, and olive oil for improved efficacy; however, knowledge regarding the antioxidant properties of black seed oil (BSO), BSO with olive oil (BSOO), and BSO with honey (BSOH) remains limited. Therefore, in this study, we investigated the antioxidant properties of BSO, BSOO, and BSOH. Gas chromatography-mass spectrometry analysis showed that BSO contained 73.48 ± 1.23 mg/kg TQ. BSO, BSOO, and BSOH exhibited remarkable antioxidant activity, with NO scavenging activities of 94.32, 76.53, and 50.37, respectively. The 2,2-diphenyl-1-picrylhydrazyl and metal chelating activity assays (with half-maximal inhibitory concentration values), oxygen radical antioxidant capacity, and total flavonoid compound content of BSO were 0.135 ± 0.003 mg/mL, 0.005 ± 0.003 mg/mL, 32 ± 0.4 μM Trolox/g extract, and 997 ± 20 mg catechin equivalent/g of extract, respectively. These results are potentially linked to the increased antioxidant activity, as suggested by Pearson's correlation coefficients. In the ferric-reducing antioxidant power assay, the highest antioxidant activity was demonstrated by BSOO and BSOH, with total phenolic content of 7288 ± 300 mM FeSO4/mg and 346 ± 17 mg of gallic acid equivalent/g E, respectively. This study affirms the potent antioxidant properties of BSO, BSOO, and BSOH, emphasizing the importance of further research on NS infusion as a promising antioxidant agent and its application as an anti-aging and tonic drug.

Gastrointestinal Effects on the Antioxidant and Immunomodulatory Properties of South African Fynbos Honey.

The Fynbos biome, Western Cape Province, South Africa, produces a unique honey from Apis mellifera capensis. The bioactivity of Fynbos (FB1-FB6) honeys and Manuka, unique manuka factor 15+ (MAN UMF15+) honey subjected to simulated in vitro digestion, was compared. The effect of each phase of digestion on the antioxidant properties and nitric oxide- (NO-) associated immunomodulatory effects was determined. The total phenolic content of MAN (UMF15+) was higher than that of FB honeys, and following digestion, the percentage bioaccessibility (BA) was 68.6% and 87.1 ± 27.0%, respectively. With the Trolox equivalent antioxidant capacity assay, the activity of FB1 and FB6 was similar to MAN (UMF15+) but reduced for FB2, FB3, FB4, and FB5 with a %BA of 77.9% for MAN (UMF15+) and 78.2 ± 13.4% for FB. The oxygen radical absorbance capacity of MAN (UMF15+) and FB honeys was similar and unaltered with digestion. In a cellular environment, using colon adenocarcinoma (Caco-2) cells, both undigested and the gastric digested honey reduced 2,2'-azobis-(2-amidinopropane) dihydrochloride- (AAPH-) mediated peroxyl radical formation. In contrast, following gastroduodenal digestion, the formation of reactive oxygen species (ROS) was increased. In murine macrophage (RAW 264.7) cells, all honeys induced different levels of NO which was significantly increased with digestion for MAN (UMF15+) and FB1. In LPS/IFN-γ stimulated RAW 264.7 macrophages, only undigested MAN (UMF15+) effectively reduced NO levels, and with digestion, NO scavenging activity of MAN (UMF15+) was reduced but increased for FB5 and FB6. In a noncellular environment, MAN (UMF15+), FB1, FB2, and FB6 scavenged NO, and with digestion, this activity was maintained. This study has identified that undigested and gastric-digested FB honey has antioxidant properties with strong potential anticancer effects following gastroduodenal digestion, related to ROS formation. MAN (UMF15+) had anti-inflammatory effects which were lost postdigestion, and in contrast, FB5 and FB6 had anti-inflammatory effects postdigestion.

In Vitro α-Glucosidase and α-Amylase Inhibition, Cytotoxicity and Free Radical Scavenging Profiling of the 6-Halogeno and Mixed 6,8-Dihalogenated 2-Aryl-4-methyl-1,2-dihydroquinazoline 3-Oxides.

Series of the 6-bromo/iodo substituted 2-aryl-4-methyl-1,2-dihydroquinazoline-3-oxides and their mixed 6,8-dihalogenated (Br/I and I/Br) derivatives were evaluated for inhibitory properties against α-glucosidase and/or α-amylase activities and for cytotoxicity against breast (MCF-7) and lung (A549) cancer cell lines. The 6-bromo-2-phenyl substituted 3a and its corresponding 6-bromo-8-iodo-2-phenyl-substituted derivative 3i exhibited dual activity against α-glucosidase (IC50 = 1.08 ± 0.02 μM and 1.01 ± 0.05 μM, respectively) and α-amylase (IC50 = 5.33 ± 0.01 μM and 1.18 ± 0.06 μM, respectively) compared to acarbose (IC50 = 4.40 ± 0.05 μM and 2.92 ± 0.02 μM, respectively). The 6-iodo-2-(4-fluorophenyl)-substituted derivative 3f, on the other hand, exhibited strong activity against α-amylase and significant inhibitory effect against α-glucosidase with IC50 values of 0.64 ± 0.01 μM and 9.27 ± 0.02 μM, respectively. Compounds 3c, 3l and 3p exhibited the highest activity against α-glucosidase with IC50 values of 1.04 ± 0.03, 0.92 ± 0.01 and 0.78 ± 0.05 μM, respectively. Moderate cytotoxicity against the MCF-7 and A549 cell lines was observed for these compounds compared to the anticancer drugs doxorubicin (IC50 = 0.25 ± 0.05 μM and 0.36 ± 0.07 μM, respectively) and gefitinib (IC50 = 0.19 ± 0.04 μM and 0.25 ± 0.03 μM, respectively), and their IC50 values are in the range of 10.38 ± 0.08-25.48 ± 0.08 μM and 11.39 ± 0.12-20.00 ± 0.05 μM, respectively. The test compounds generally exhibited moderate to strong antioxidant capabilities, as demonstrated via robust free radical scavenging activity assays, viz., DPPH and NO. The potential of selected derivatives to inhibit superoxide dismutase (SOD) was also investigated via enzymatic assay in vitro. Molecular docking revealed the N-O moiety as essential to facilitate electrostatic interactions of the test compounds with the protein residues in the active site of α-glucosidase and α-amylase. The presence of bromine and/or iodine atoms resulted in increased hydrophobic (alkyl and/or π-alkyl) interactions and therefore increased inhibitory effect against both enzymes.