Presence Of Reactive Oxygen Species Research Articles

Effects of swimming activity and feed restriction on antioxidant and digestive enzymes in juvenile rainbow trout: Implications for nutritional and exercise strategies in aquaculture.

In this study, we investigated the effects of swimming activity and feed restriction on digestion and antioxidant enzyme activities in juvenile rainbow trout (average body weight of 26.54±0.36g). The stomach, liver and kidney tissues were obtained from four distinct groups: the static water group (fish were kept in static water and fed to satiation), the feeding restricted group (fish were kept in static water with a 25% feed restriction), the swimming exercised group (fish were forced to swimming at a flow rate of 1 Body Length per second (BL/s)) and the swimming exercised-feed restricted group (subjected to swimming exercise at a 1BL/s flow rate along with a 25% feed restriction). We determined the levels of glutathione, lipid peroxidation and the activities of catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase and lactate dehydrogenase, as well as the presence of reactive oxygen species in the tissues obtained from the fish. Additionally, the activities of pepsin, protease, lipase and arginase in these tissues were measured. Swimming activity and feed restriction showed different effects on the enzyme activities of the fish in the experimental groups. It can be concluded that proper nutrition and exercise positively influence the antioxidant system and enzyme activities in fish, reducing the formation of free radicals. This situation is likely to contribute to the fish's development.

Metabolic Roles of HIF1, c-Myc, and p53 in Glioma Cells

The metabolic reprogramming that promotes tumorigenesis in glioblastoma is induced by dynamic alterations in the hypoxic tumor microenvironment, as well as in transcriptional and signaling networks, which result in changes in global genetic expression. The signaling pathways PI3K/AKT/mTOR and RAS/RAF/MEK/ERK stimulate cell metabolism, either directly or indirectly, by modulating the transcriptional factors p53, HIF1, and c-Myc. The overexpression of HIF1 and c-Myc, master regulators of cellular metabolism, is a key contributor to the synthesis of bioenergetic molecules that mediate glioma cell transformation, proliferation, survival, migration, and invasion by modifying the transcription levels of key gene groups involved in metabolism. Meanwhile, the tumor-suppressing protein p53, which negatively regulates HIF1 and c-Myc, is often lost in glioblastoma. Alterations in this triad of transcriptional factors induce a metabolic shift in glioma cells that allows them to adapt and survive changes such as mutations, hypoxia, acidosis, the presence of reactive oxygen species, and nutrient deprivation, by modulating the activity and expression of signaling molecules, enzymes, metabolites, transporters, and regulators involved in glycolysis and glutamine metabolism, the pentose phosphate cycle, the tricarboxylic acid cycle, and oxidative phosphorylation, as well as the synthesis and degradation of fatty acids and nucleic acids. This review summarizes our current knowledge on the role of HIF1, c-Myc, and p53 in the genic regulatory network for metabolism in glioma cells, as well as potential therapeutic inhibitors of these factors.

Electrochemiluminescence-Based Single-Particle Tracking of the Biomolecules Moving along Intercellular Membrane Nanotubes between Live Cells.

Electrochemiluminescence (ECL) imaging, a rapidly evolving technology, has attracted significant attention in the field of cellular imaging. However, its primary limitation lies in its inability to analyze the motion behaviors of individual particles in live cellular environments. In this study, we leveraged the exceptional ECL properties of quantum dots (QDs) and the excellent electrochemical properties of carbon dots (CDs) to develop a high-brightness ECL nanoprobe (CDs-QDs) for real-time ECL imaging between living cells. This nanoprobe has excellent signal-to-noise ratio imaging capabilities for the single-particle tracking (SPT) of biomolecules. Our finding elucidated the enhanced ECL mechanism of CDs-QDs in the presence of reactive oxygen species through photoluminescence, electrochemistry, and ECL techniques. We further tracked the movement of single particles on membrane nanotubes between live cells and confirmed that the ECL-based SPT technique using CD-QD nanoparticles is an effective approach for monitoring the transport behaviors of biomolecules on membrane nanotubes between live cells. This opens a promising avenue for the advancement of ECL-based single-particle detection and the dynamic quantitative imaging of biomolecules.

Quest for a stable Cu-ligand complex with a high catalytic activity to produce ROS.

Metal ion-catalysed overproduction of reactive oxygen species (ROS) are believed to contribute significantly to oxidative stress and be involved in several biological processes, from immune defence to development of diseases. Among the essential metal ions, copper is one of the most efficient catalysts in ROS production in the presence of O2 and a physiological reducing agent such as ascorbate. To control this chemistry, Cu ions are tightly coordinated to biomolecules. Free or loosely bound Cu ions are generally avoided to prevent their toxicity. In the present report, we aim to find stable Cu-ligand complexes (Cu-L) that can catalyse efficiently the production of ROS in presence of ascorbate under aerobic conditions. Thermodynamic stability would be needed to avoid dissociation in biological environment and high ROS catalysis is of interest for applications as in antimicrobial or anticancer agents. A series of Cu complexes with the well-known tripodal and tetradentate ligands containing a central amine linked to three pyridyl-alkyl arms of different lengths were investigated. The two of them with mixed armlength showed higher catalytic activity in oxidation of ascorbate and subsequent ROS production than Cu salts in buffer, which is an unprecedented result. Despite these high catalytic activities, no increased antimicrobial activity towards E. coli or cytotoxicity against eukaryotic AGS cells in culture related to Cu-L based ROS production could be observed. The potential reasons for discrepancy between in vitro and in cell data will be discussed.

Role of airway epithelium in viral respiratory infections: Can carbocysteine prevent or mitigate them?

Alterations in airway epithelial homeostasis increase viral respiratory infections risk. Viral infections frequently are associated with chronic obstructive pulmonary disease (COPD) exacerbations, events that dramatically promote disease progression. Mechanism promoting the main respiratory viruses entry and virus-evocated innate and adaptive immune responses have now been elucidated, and an oxidative stress central role in these pathogenic processes has been recognized. Presence of reactive oxygen species in macrophages and other cells allows them to eliminate virus, but its excess alters the balance between innate and adaptive immune responses and proteases/anti-proteases and leads to uncontrolled inflammation, tissue damage, and hypercoagulability. Different upper and lower airway cell types also play a role in viral entry and infection. Carbocysteine is a muco-active drug with anti-oxidant and anti-inflammatory properties used for the management of several chronic respiratory diseases. Although the use of anti-oxidants has been proposed as an effective strategy in COPD exacerbations management, the molecular mechanisms that explain carbocysteine efficacy have not yet been fully clarified. The present review describes the most relevant features of the common respiratory virus pathophysiology with a focus on epithelial cells and oxidative stress role and reports data supporting a putative role of carbocysteine in viral respiratory infections.

Natural Disinfection-like Process Unveiled in Soil Microenvironments by Enzyme-Catalyzed Chlorination.

Substantial natural chlorination processes are a growing concern in diverse terrestrial ecosystems, occurring through abiotic redox reactions or biological enzymatic reactions. Among these, exoenzymatically mediated chlorination is suggested to be an important pathway for producing organochlorines and converting chloride ions (Cl-) to reactive chlorine species (RCS) in the presence of reactive oxygen species like hydrogen peroxide (H2O2). However, the role of natural enzymatic chlorination in antibacterial activity occurring in soil microenvironments remains unexplored. Here, we conceptualized that heme-containing chloroperoxidase (CPO)-catalyzed chlorination functions as a naturally occurring disinfection process in soils. Combining antimicrobial experiments and microfluidic chip-based fluorescence imaging, we showed that the enzymatic chlorination process exhibited significantly enhanced antibacterial activity against Escherichia coli and Bacillus subtilis compared to H2O2. This enhancement was primarily attributed to in situ-formed RCS. Based on semiquantitative imaging of RCS distribution using a fluorescence probe, the effective distance of this antibacterial effect was estimated to be approximately 2 mm. Ultrahigh-resolution mass spectrometry analysis showed over 97% similarity between chlorine-containing formulas from CPO-catalyzed chlorination and abiotic chlorination (by sodium hypochlorite) of model dissolved organic matter, indicating a natural source of disinfection byproduct analogues. Our findings unveil a novel natural disinfection process in soils mediated by indigenous enzymes, which effectively links chlorine-carbon interactions and reactive species dynamics.

Sasanquasaponin from Camellia oleifera Abel Exerts an Anti-Inflammatory Effect in RAW 264.7 Cells via Inhibition of the NF-κB/MAPK Signaling Pathways.

Sasanquasaponin (SQS), a secondary metabolite that is derived from Camellia seeds, reportedly possesses notable biological properties. However, the anti-inflammatory effects of SQS and its underlying mechanisms remain poorly explored. Herein, we aimed to investigate the anti-inflammatory properties of SQS against lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells, focusing on the nuclear factor-κB (NF-κB) and MAPK signaling pathways. SQS was isolated using a deep eutectic solvent and D101 macroporous adsorption resin and analyzed using high-performance liquid chromatography. The viability of LPS-stimulated RAW264.7 was assessed using the CCK-8 assay. The presence of reactive oxygen species (ROS) was evaluated using 2',7'-dichlorofluorescein-diacetate. The expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) were detected using reverse transcription-quantitative PCR and ELISA. Western blot was performed to analyze the protein expression of LPS-induced RAW264.7 cells. Herein, SQS exhibited anti-inflammatory activity: 30 μg/mL of SQS significantly reduced ROS generation, inhibited the LPS-induced expression of iNOS and COX-2, and attenuated the production of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. The anti-inflammatory activity was potentially mediated by inhibiting the phosphorylation of IκBα and p65 in the NF-κB signaling pathway and the phosphorylation of ERK and JNK in the MAPK signaling pathway. Accordingly, SQS could inhibit inflammation in LPS-induced RAW264.7 cells by suppressing the NF-κB and MAPK signaling pathways. This study demonstrated the potential application of SQS as an anti-inflammatory agent.

Evaluation of Oxidative and Nitrosative Stress Markers Related To Inflammation in The Cumulus Cells and Follicular Fluid of Women Undergoing Intracytoplasmic Sperm Injection: A Prospective Study.

Oxidative/nitrosative stress in the oocyte microenvironment could have an impact on intracytoplasmic sperm injection (ICSI) outcomes. The presence of reactive oxygen species (ROS) and reactive nitrogen species (RNS) can stimulate the secretion of pro-inflammatory cytokines, leading to chronic inflammation and potentially affecting embryo as well as oocyte quality. This study aimed to examine the relationship of lipid peroxidation [measured by the malondialdehyde (MDA) assay] with protein carbonyl [measured by the 2,4 dinitrophenylhydrazine (DNPH) assay] levels in cumulus cells (CCs), as well as nitric oxide (NO), peroxynitrite (ONOO-), and C-reactive protein (CRP) levels in follicular fluid (FF). The potential relationship of these levels with ICSI outcome was also evaluated. In this prospective study, 63 FF samples and their corresponding CCs were collected for ICSI procedures. Spectrophotometry was used to assess levels of DNPH, MDA, NO, and ONOO-. CRP levels were evaluated using an immunoturbidimetric assay. The patients under 37 years with normal ovarian reserve had significantly lower levels of MDA, DNPH, NO, ONOO-, and CRP compared to those over 37 years. Additionally, we observed higher levels of MDA, DNPH, NO, ONOO-, and CRP in the group with an oocyte maturity rate of less than 60%. No significant difference was observed between the DNPH levels and factors such as infertility duration, embryo quality, pregnancy, or the number of retrieved oocytes. A higher level of MDA, NO, ONOO-, and CRP was found to be significantly related to the lower number of retrieved oocytes, longer periods of infertility, poor embryo quality, and negative pregnancy outcomes. Oxidative/nitrosative stress, linking to inflammation in the oocyte microenvironment, can be considered as a potentially useful biomarker for assessing the development and competence of oocytes and embryos and predicting ICSI outcomes.

Defects materials of Institut Lavoisier-125(Ti) materials enhanced photocatalytic activity for toluene and chlorobenzene mixtures degradation: Mechanism study

In this paper, the effect of three monocarboxylic acids on MIL-125 synthesis was systematically investigated and the results were discussed in detail. X-ray diffractometry (XRD) and nitrogen adsorption–desorption curves indicated that small molecule acids (acetic acid, propionic acid and butyric acid) affected the morphology of MIL-125 and induced lamellar pores and structural defects in the crystals. Thermogravimetric measurements confirmed the presence of acid-regulated defective metal–organic frameworks (MOFs). Electrochemical tests and density function theory calculations indicated that acid modulation could change the forbidden bandwidth of the material. The acid modification strategy effectively promoted the transfer of photogenerated electrons and enhanced the adsorption and activation of O2 and H2O molecules, generating reactive radicals. The modified MOFs also showed excellent performance in the removal of mixed toluene and chlorobenzene. The degradation pathways of the mixture were analyzed by in situ infrared (IR) and gas chromatography-mass spectrometry (GC–MS). The mixture was converted to chlorophenolic intermediates in the presence of reactive oxygen species, further decomposed to form ethers and ethanol, and finally formed small molecules such as carbon dioxide and water. A feasible method was provided for the preparation of photocatalysts for the treatment of mixed VOCs.

Periodontal disease etiology and role of oxidative stress

The term "periodontal disease" is used to describe an array of inflammatory conditions that can affect the periodontium. In response to the challenge given by the bacteria, the gingival and periodontal tissues undergo a complicated chain of events involving communication It is between the membranes of a vital nature located under the gums and the person's immune inflammatory reaction. When there is an imbalance between the oxidants and the antioxidants in the body, this is known as oxidative stress. Antioxidants are compounds that may either seek out and destroy oxidants or prevent them from forming in the first place. Some of the oxidants produced by-products of normal cellular metabolism include reactive oxygen species and reactive nitrogen species. These byproducts are known as reactive oxygen and reactive nitrogen species, respectively. The presence of reactive oxygen species (ROS) has been shown to be associated with periodontal disease in research.

The impact of dietary Laminaria digitata and alginate lyase supplementation on the weaned piglet liver: A comprehensive proteomics and metabolomics approach

The brown seaweed Laminaria digitata, a novel feedstuff for weaned piglets, has potentially beneficial prebiotic properties. However, its recalcitrant cell wall challenges digestion in monogastrics. Alginate lyase is a promising supplement to mitigate this issue. This study's aim was to investigate the impact of incorporating 10% dietary Laminaria digitata, supplemented with alginate lyase, on the hepatic proteome and metabolome of weaned piglets. These diets introduced minor variations to the metabolome and caused significant shifts in the proteome. Dietary seaweed provided a rich source of n-3 PUFAs that could signal hepatic fatty acid oxidation (FABP, ACADSB and ALDH1B1). This may have affected the oxidative stability of the tissue, requiring an elevated abundance of GST for regulation. The presence of reactive oxygen species likely inflicted protein damage, triggering increased proteolytic activity (LAPTM4B and PSMD4). Alginate lyase supplementation augmented the number of differentially abundant proteins, which included GBE1 and LDHC, contributing to maintain circulating glucose levels by mobilizing glycogen stores and branched-chain amino acids. The enzymatic supplementation with alginate lyase amplified the effects of the seaweed-only diet. An additional filter was employed to test the effect of missing values on the proteomics analysis, which is discussed from a technical perspective. SignificanceBrown seaweeds such as Laminaria digitata have prebiotic and immune-modulatory components, such as laminarin, that can improve weaned piglet health. However, they have recalcitrant cell wall polysaccharides, such as alginate, that can elicit antinutritional effects on the monogastric digestive system. The aim of this study was to evaluate the effect of a high level of dietary L. digitata and alginate lyase supplementation on the hepatic metabolism of weaned piglets, using high throughput Omics approaches.

Electrochemical, Microstructural and Mechanical Investigations of H2O2-Driven Degradation of Ti6Al4V

Titanium and its alloys consitute one of the main classes of materials utilized as non-biodegradable implants in the human body. The corrosion resistance of titanium is mainly due to the presence of a thin, compact and passive layer on its surface. However, this layer degrades in the presence of reactive oxygen species, such as oxygen peroxide (H2O2) [1,2]. This leads to the device degradation and the release of its constituents in the surrounding tissues, which may bring about serious health issues (peri-implantitis, osteolysis, neurotoxicity...) [3]. H2O2 is produced by the immune system during inflammatory episodes by specific enzymes, such as NADPH oxidase and superoxide dismutase [4]. It is also utilized by surgeons at high concentrations (ca. 1 M) during peri-implant tissue disinfection. Ti6Al4V (titanium grade 5, an α + β alloy) is a popular implant material because of its excellent mechanical properties. However, in recent years, Ti6Al4V with equiaxed α grains (and β phase located at the grain boundaries) was reported to undergo a significant degradation by H2O2 characterized by the growth of a thick oxide layer on the α grains and the development of porosity and cracks in the β phase [1]. Ti6Al4V could be susceptible to stress corrosion cracking (SCC) under mechanical load due to the β phase dissolution in H2O2-containing physiological solutions (Figure 1). However, no clear link has been established yet between the corrosive environment, the mechanical load and the microstructure of the Ti6Al4V alloy.This contribution will report about the influence of H2O2 concentration on the in vitro corrosion of Ti6Al4V simulating inflammation conditions (low concentration) as well as disinfection procedures (high concentrations). Results on the electrochemical behavior (monitored by impedance spectroscopy), the degraded microstructure (obtained with focused ion beam scanning electron microscopy and transmission electron microscopy) and the impact of the H2O2-driven degradation on the mechanical properties of the alloy will be presented and discussed.Acknowledgements:The authors gratefully acknowledge the financial support of the French National Research Agency (grant agreement ANR-22-CE93-0007-02) and that of the Swiss National Science Foundation (grant agreement 200021L_213161).

Inhibitory effect and action mechanism of perillaldehyde on the Fusarium graminearum in postharvest fresh ginger

Perillaldehyde, the predominant antimicrobial compound found in Perilla, offers a safe and highly efficient solution for the preservation of fruits and vegetables. This study delved into the inhibitory potential of perillaldehyde against Fusarium graminearum, the primary postharvest pathogen affecting ginger. The current research encompassed both in vitro and in vivo investigations. Our results revealed that the minimum inhibitory concentration of perillaldehyde required to combat F. graminearum was 240 µL·L−1. At this concentration, perillaldehyde exhibited remarkable efficacy in reducing ginger disease rates, with a staggering 99.9% inhibition in mycelium growth. Furthermore, perillaldehyde disrupted the integrity of the fungal cell membrane, hence elevated outer membrane permeability. This resulted in the leakage of proteins, sugars, nucleic acids, and an increase in electrical conductivity within F. graminearum. Notably, perillaldehyde treatment led to a substantial increase in malondialdehyde content in F. graminearum, which was 2.5 times higher than the control group. It also significantly reduced ergosterol content and ATPase activity by 87% and 85%, respectively. The presence of reactive oxygen species (ROS) increased, exacerbating membrane peroxidation damage. Electron microscopy unveiled the transformative impact of perillaldehyde on F. graminearum. Perillaldehyde induced extensive shrinkage, morphological thinning, spatial structure folding, and the leakage of essential cell nutrients, cell wall membranes, and organelle damage. In summary, perillaldehyde's mode of action disrupts the energy supply and metabolism of mycelia, ultimately inducing apoptosis and proving to be a potent inhibitor of F. graminearum. Its application in preserving fresh ginger effectively extended the nutritional quality of the product, demonstrating its potential as an efficient preservative. This biological preservation technique offers convenience over traditional physical methods and addresses concerns related to chemical residue, thereby opening new avenues for ginger green preservation technology.

Fullerene C60-chitosan conjugate applied in the photoinactivation of Staphylococcus aureus

A novel fullerene/chitosan (C60-CS) conjugate was synthesized. The addition reaction of the amine groups of chitosan (CS) to fullerene (C60) was carried out in N,N-dimethylformamide (DMF), and triethylamine at room temperature. The conjugate C60-CS was purified by dialysis in water. C60-CS showed an absorption spectrum characteristic of modified fullerenes. The ability to produce O2(1Δg) was determined by the decomposition of 9,10-dimethylanthracene (DMA) in DMF, finding a quantum yield value of 0.07. Besides, to obtain information about the contributions of the photoreaction mechanisms, the L-tryptophan photodecomposition was studied in the presence of reactive oxygen species (ROS) scavengers, such as D-mannitol and sodium azide. The results indicated a significant contribution of the type II mechanism to the photooxidation of the amino acid. This effect was confirmed by studies of the kinetics of nitrotetrazolium blue photoreduction in the presence of nicotinamide adenine dinucleotide. This conjugate's photodynamic inactivation (PDI) capacity was investigated in Staphylococcus aureus. The photodynamic effect induced a 4 log decrease in cell viability when the cells were treated with 10 μM C60-CS and 30 min of irradiation with white light. The photoreaction mechanisms involved in the photosensitized inactivation of S. aureus by C60-CS were studied with the addition of azide ions, deuterated saline water, D-mannitol, and potassium iodide. It was confirmed that the photodynamic action of C60-CS was mainly mediated by type II photoprocess. Photooxidation of DMA induced by C60-CS in S. aureus cells indicated the production of O2(1Δg) in this biological medium. Finally, PDI studies were performed on agar surfaces, treating the cells with C60-CS before deposition on the surface. The subsequent inactivation of S. aureus sensitized by C60-CS after 30 min of irradiation with white light produced a marked elimination of bacteria as a function of increasing concentration. Therefore, this conjugate is a promissory photosensitizing agent to inactivate S. aureus.

A Comparison of ICSI Outcomes and Reactive Oxygen Species Levels in Seminal Plasma between Normozoospermia and Sperm Abnormalities Groups for Infertile Men

Background: Social life and the healthcare systems are affected by infertility. Infertility could be primary or secondary; secondary infertility is the inability to conceive after one successful pregnancy while primary infertility is the inability to conceive at all. As sperm abnormalities cause male infertility, Intracytoplasmic Sperm Injection (ICSI) is a particular type of in vitro fertilization (IVF) used to treat severe male-factor infertility. Free radical oxygen derivatives are reactive oxygen species (ROS). Reactive oxygen species may cause 30% to 80% of male infertility.  Aims of the study: the present study aims to determine the reactive oxygen species level in seminal plasma and to study the Intracytoplasmic Sperm Injection outcomes for Normospermia group and compare it with Oligozoospermia, Asthenozoospermia and the Teratozoospermia Groups.  Material, and Methods: a cross-sectional study was conducted between January 2023 to June 2023 in Najaf, on a non-random sampling including 50 couples who suffered from a minimum of 12 months of primary fertility with regular unprotected sexual intercourse and who had attended the fertility center in Najaf requesting fertility treatment. A gynecological examination and assessment were done for the female participants while the urologists examined and assessed the male subjects; then, a semen analysis was carried out followed by macroscopic and microscopic examinations. After the preparation of the sample for ICSI and performing ICSI, pregnancy was assessed and the outcomes of the different groups were compared. At the same time, reactive oxygen species levels were assessed by using the Human Reactive Oxygen Species ELISA kit. Then, the SPSS version 26 was used to perform the statistical analysis. Results: Among the twenty-one patients with Normozoospermia, seven with Asthenospermic, seven with Oligozoospermia and fifteen with Teratozoospermia,  there was a significant difference among the four groups regarding sperm concentration, progressive motility, and sperm normal morphology. There was no significant difference among the type of sperm, Normo, Astheno, Tearato, and Oligozoospermia, regarding birth rate and ICSI outcomes. Males with higher progressive motility showed a higher pregnancy rate. In conclusion, despite the presence of reactive oxygen species, Intracytoplasmic Sperm Injection was advantageous and effective for all four groups. reactive oxygen species had no significant effect on Intracytoplasmic Sperm Injection outcomes, however Normozoospermia was associated with greater pregnancy rates. Despite the presence of reactive oxygen species, Intracytoplasmic Sperm Injection was advantageous and effective for all four groups. ROS had no significant effect on Intracytoplasmic Sperm Injection outcomes, however Normozoospermia was associated with greater pregnancy rates.

Oxidative Stress in Pregnancy.

Recent years have seen an increased interest in the role of oxidative stress (OS) in pregnancy. Pregnancy inherently heightens susceptibility to OS, a condition fueled by a systemic inflammatory response that culminates in an elevated presence of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the circulatory system. The amplified OS in pregnancy can trigger a series of detrimental outcomes such as underdevelopment, abnormal placental function, and a host of pregnancy complications, including pre-eclampsia, embryonic resorption, recurrent pregnancy loss, fetal developmental anomalies, intrauterine growth restriction, and, in extreme instances, fetal death. The body's response to mitigate the uncontrolled increase in RNS/ROS levels requires trace elements that take part in non-enzymatic and enzymatic defense processes, namely, copper (Cu), zinc (Zn), manganese (Mn), and selenium (Se). Determination of ROS concentrations poses a challenge due to their short half-lives, prompting the use of marker proteins, including malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), and glutathione (GSH). These markers, indicative of oxidative stress intensity, can offer indirect assessments of pregnancy complications. Given the limitations of conducting experimental studies on pregnant women, animal models serve as valuable substitutes for in-depth research. This review of such models delves into the mechanism of OS in pregnancy and underscores the pivotal role of OS markers in their evaluation.

Green synthesis of iron oxide nanoparticles from Spermacoce ocymoides Burm.f. plant extracts for targeted lung cancer A549 cell therapy

The present study evaluated the synthesis of iron oxide nanoparticles using Spermacoce ocymoides Burm.f. plant extracts, and the effects of plant based iron oxide nanoparticles on A549 lung cancer cells were investigated to elucidate their impact on cellular morphology, mitochondrial function, and apoptotic pathways. Spermacoce ocymoides plant based iron oxide nanoparticles were characterised by X-ray diffraction, Atomic force microscopy, FTIR, and UV-Vis absorption spectroscopy. Iron oxide nanoparticle treatment caused considerable morphological alterations in A549 cells, including cell shrinkage, detachment, membrane blabbing, and distorted shape, consistent with cellular stress and potential apoptotic events. MMP analysis revealed a dose-dependent decrease in mitochondrial membrane potential, implying that nanoparticles have an effect on mitochondrial function. The presence of reactive oxygen species suggested that oxidative stress was involved in the cellular response to iron oxide nanoparticles. Additionally, DNA fragmentation analysis confirmed the activation of apoptotic pathways, with the nanoparticles themselves serving as a positive control for inducing apoptosis. The observed morphological changes, altered mitochondrial function, ROS production, and DNA fragmentation collectively point towards apoptotic cell death pathways being triggered by the nanoparticles.
 KEY WORDS: Spermacoce ocymoides, Iron oxide nanoparticles, A549 cells, Apoptotic
 Bull. Chem. Soc. Ethiop. 2024, 38(1), 123-134. DOI: https://dx.doi.org/10.4314/bcse.v38i1.10

Self-assembly of PEG-PPS polymers and LL-37 peptide nanomicelles improves the oxidative microenvironment and promotes angiogenesis to facilitate chronic wound healing.

Refractory diabetic wounds are associated with high incidence, mortality, and recurrence rates and are a devastating and rapidly growing clinical problem. However, treating these wounds is difficult owing to uncontrolled inflammatory microenvironments and defective angiogenesis in the affected areas, with no established effective treatment to the best of our knowledge. Herein, we optimized a dual functional therapeutic agent based on the assembly of LL-37 peptides and diblock copolymer poly(ethylene glycol)-poly(propylene sulfide) (PEG-PPS). The incorporation of PEG-PPS enabled responsive or controlled LL-37 peptide release in the presence of reactive oxygen species (ROS). LL-37@PEG-PPS nanomicelles not only scavenged excessive ROS to improve the microenvironment for angiogenesis but also released LL-37 peptides and protected them from degradation, thereby robustly increasing angiogenesis. Diabetic wounds treated with LL-37@PEG-PPS exhibited accelerated and high-quality wound healing in vivo. This study shows that LL-37@PEG-PPS can restore beneficial angiogenesis in the wound microenvironment by continuously providing angiogenesis-promoting signals. Thus, it may be a promising drug for improving chronic refractory wound healing.

Dual Tunability for Uncatalyzed N-Alkylation of Primary Amines Enabled by Plasma-Microdroplet Fusion.

The fusion of non-thermal plasma with charged microdroplets facilitates catalyst-free N-alkylation for a variety of primary amines, without halide salt biproduct generation. Significant reaction enhancement (up to >200×) is observed over microdroplet reactions generated from electrospray. This enhancement for the plasma-microdroplet system is attributed to the combined effects of energetic collisions and the presence of reactive oxygen species (ROS). The ROS (e.g., O2•-) act as a proton sink to increase abundance of free neutral amines in the charged microdroplet environment. The effect of ROS on N-alkylation is confirmed through three unique experiments: (i) utilization of radical scavenging reagent, (ii) characterization of internal energy distribution, and (iii) controls performed without plasma, which lacked reaction acceleration. Establishing plasma discharge in the wake of charged microdroplets as a green synthetic methodology overcomes two major challenges within conventional gas-phase plasma chemistry, including the lack of selectivity and product scale-up. Both limitations are overcome here, where dual tunability is achieved by controlling reagent concentration and residence time in the microdroplet environment, affording single or double N-alkylated products. Products are readily collected yielding milligram quantities in eight hours. These results showcase a novel synthetic strategy that represents a straightforward and sustainable C-N bond-forming process.

Dual Tunability for Uncatalyzed N‐Alkylation of Primary Amines Enabled by Plasma‐Microdroplet Fusion

AbstractThe fusion of non‐thermal plasma with charged microdroplets facilitates catalyst‐free N‐alkylation for a variety of primary amines, without halide salt biproduct generation. Significant reaction enhancement (up to >200×) is observed over microdroplet reactions generated from electrospray. This enhancement for the plasma‐microdroplet system is attributed to the combined effects of energetic collisions and the presence of reactive oxygen species (ROS). The ROS (e.g., O2⋅−) act as a proton sink to increase abundance of free neutral amines in the charged microdroplet environment. The effect of ROS on N‐alkylation is confirmed through three unique experiments: (i) utilization of radical scavenging reagent, (ii) characterization of internal energy distribution, and (iii) controls performed without plasma, which lacked reaction acceleration. Establishing plasma discharge in the wake of charged microdroplets as a green synthetic methodology overcomes two major challenges within conventional gas‐phase plasma chemistry, including the lack of selectivity and product scale‐up. Both limitations are overcome here, where dual tunability is achieved by controlling reagent concentration and residence time in the microdroplet environment, affording single or double N‐alkylated products. Products are readily collected yielding milligram quantities in eight hours. These results showcase a novel synthetic strategy that represents a straightforward and sustainable C−N bond‐forming process.