Oxidation Of Substances Research Articles

Analysis of Redox Reaction of Caffeic Acid Under UV Irradiation By Electrochemical Measurements

IntroductionSince the discovery of the French Paradox, focus on polyphenols as substances with health benefits has continued to increase. Caffeic acid (Caf, 3,4-dihydroxycinnamic acid), the subject of this study, has also focused on as a polyphenol with antioxidant activity to prevent diseases caused by reactive oxygen species. Caf is one of the major antioxidants and is present in a variety of plants, making it easily available. We have extensively studied the electrochemical properties of polyphenols including caffeic acid[1-4]. We have found that cyclic voltammograms (CV) of Caf exhibit a unique behavior in which the oxidation current increases and the reduction current decreases when the electrode is irradiated with UV light. It is known that the trans-alkene moiety of the side chain of Caf is isomerized to the cis form upon UV irradiation[5], and it is also known that the cis form is converted to esculetin[6]. Based on these findings, we investigated the mechanism of the oxidation reaction of Caf under UV irradiation. Experiments A water/methanol (MeOH) (50/50, v/v) mixed solution containing 0.25 mM trans-Caf and 0.1 M citrate buffer (pH 6.0) was used as a sample solution. Cyclic voltammograms (CV) were obtained while irradiating the electrode surface with UV light. UV light from an Hg lamp was irradiated to the sample solution with the wavelength controlled by a bandpass filter. The UV-irradiated solution contained the trans- and cis-Caf, which were separated by HPLC and detected by UV absorption and electrochemical detector (ECD). A water/MeOH (85/15, v/v) mixed solution containing 0.085% (v/v) formic acid was used as an eluent for HPLC measurements. A flow whole-electrolytic cell was used as an ECD. Results and Discussion When the UV-irradiated solution was analyzed by HPLC, trans-Caf, cis-Caf, and esculetin were detected. The CVs during UV irradiation showed that the wavelength that most contributes to the isomerization of Caf was at 330 nm, which was the absorption peak derived from the trans-alkene chain of the side chain of trans-Caf. In contrast, at 260 nm where there was almost no absorption of trans-Caf, the oxidation current corresponding to cis form was very small. These results show that the isomerization of Caf was dependent on the absorption spectrum of trans-Caf. The results of coulometry using the flow whole-electrolytic cell showed that the number of electrons through the oxidation, n of trans-Caf, cis-Caf, and esculetin were 2.0, 4.4, and 4.4, respectively. These n-values indicated that the oxidation of cis-Caf and esculetin were not stop at quinone form (n = 2), but were further oxidized. Furthermore, the results of multi-scan CV using an HPLC-electrolytic cell (Figure 1) indicated that in the first cycle (black line), cis-Caf underwent a two-step oxidation reaction, the first step being irreversible and the second step reversible. The peak potential of the first step oxidation was more negative than that of trans-Caf, and that of the second step of cis-Caf was more negative than that of esculetin. In other words, it was found that an easily oxidizable substance with a lower oxidation-reduction potential than the trans-Caf was produced. From these results, cis-Caf produced by UV irradiation is suggest to have higher antioxidant activity than trans-Caf.

Characterization of Disinfection By-Products Originating from Residual Chlorine-Based Disinfectants in Drinking Water Sources.

In this study, samples from the Yangtze River, Han River, and Liangzi Lake in Wuhan City were utilized to characterize the formation of disinfection by-products (DBPs) from chlorine-based disinfection residues in drinking water sources. The results indicated that the main DBPs in drinking water sources were trichloromethane (TCM) and trichloroacetic acid (TCAA). The generation of DBPs was significantly positively correlated with oxidative substances, aromatic compounds, pH, and ammonia nitrogen (NH3-N) content in the water. The concentration of TCAA increased from 0 to 2.45 ± 0.31 mg/L when the reaction time increased to 72 h. As the NaClO concentration increased from 5 mg/L to 15 mg/L, the concentrations of TCAA, TBM, and DCAN increased from 2.03 ± 0.04 mg/L, 0 mg/L, and 0 mg/L to 2.49 ± 0.34 mg/L, 0.21 ± 0.07 mg/L, and 0.10 ± 0.04 mg/L before decreasing to 1.75 ± 0.19 mg/L, 0.17 ± 0.07 mg/L, and 0.04 ± 0.05 mg/L, respectively. The orthogonal experimental results showed that Br-, NH3-N, and pH all had significant influences on the TCM generation, whereas temperature affected the formation of TCAA in the Han River. This work reveals the factors influencing the generation of DBPs from chlorine-based disinfection residues, offering a prevention and control method for DBPs in drinking water sources from a theoretical perspective.

Sorption Properties of Bentonite-Based Organoclays with Amphoteric and Nonionic Surfactants in Relation to Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic hydrocarbons (PAHs) are a major scientific challenge due to their profound impact on public and environmental health. Therefore, studying ways to detoxify PAHs is important. In this research, the adsorption ability of bentonite modified with five surfactants, including amphoteric (cocoamphodiacetate disodium and sodium cocoiminodipropionate) and nonionic (lauramine oxide, cocamide diethanolamine, and alkylpolyglucoside) substances for the adsorption of high-molecular benzo(a)pyrene and low-molecular naphthalene from the PAH group was studied. The bentonite and bentonite-based organoclays were characterized using X-ray diffraction and Fourier transform infrared spectroscopy. The results showed that the maximum adsorption of benzo(a)pyrene by organoclays increased compared with the initial mineral. The adsorption of benzo(a)pyrene is higher than that of naphthalene. The adsorption process of benzo(a)pyrene by bentonite and organoclays is predominantly monolayer, as it is better described by the Langmuir model (R2 0.77–0.98), while naphthalene is predominantly multilayer, described by the Freundlich model (R2 0.86–0.96). According to the effectiveness of sorption capacities of organoclays—including the degree of sorption, Langmuir and Freundlich constants, the value of maximum adsorption, Gibbs free energy, and the index of favorability of the adsorption process—the most effective modification was found. For the adsorption of benzo(a)pyrene the best was cocoamphodiacetate disodium, and for naphthalene it was sodium cocoiminodipropionate.

Root physiological and morphology processes co-regulate the growth of Chinese-fir saplings in response to warming and precipitation reduction in the sub-tropical regions

Subtropical China is projected to experience elevated temperature greater than the mean global temperature increase and is accompanied by reduced precipitation. The plasticity of roots to changing environment strongly influences ecosystem feedbacks to climate change. However, knowledge gaps on the individual and combined effects of warming and precipitation reduction on root systems hinder our ability to accurately predict the growth and adaptability of forests under future climate change. To examine the effects of warming (W) and precipitation reduction (P) on roots physiology and morphology of Chinese-fir saplings, we used a randomized complete block design with factorial soil warming (ambient, ambient + 5℃) and precipitation reduction (ambient, ambient-50 %) treatments. A full excavation method was adopted to obtain roots, then we measured the root physiology (osmoregulatory substances, oxidant substances, protective enzymes, endogenous hormones), morphology (specific root length, SRL; surface root area, SRA; root tissue density, RTD). The content of carbon and nitrogen, isotopes (δ13C and δ15N); soil temperature, soil moisture and sapling growth were also measured. We found that compared with the control, W decreased the abscisic acid (IAA) content; P increased the contents of hydrogen peroxide (H2O2) and proline (Pro), and decreased the contents of IAA and cytokinin (CTK); warming plus precipitation reduction (WP) increased the Pro content, and decreased the contents of IAA and CTK. In addition, the effects of W and P on root morphology varied with soil depth and root diameter class. W, P, and WP all increased fine root SRL and SRA in deep soil. Warming and precipitation reduction could affect physiological traits (e.g. non-enzymatic substances and antioxidant enzymes) and subsequently morphological traits via influencing soil environment and root tissue chemistry. Collectively, the results indicated that Chinese-fir saplings responded to warming and precipitation reduction by comprehensive regulation of the non-enzymatic substances (e.g., osmotic substances and endogenous hormones) of fine roots and changing root morphological characteristics in deep soil.

Increased formation of brominated disinfection by-products and toxicities during low-H2O2-mediated ozonation of reclaimed water

Reusing reclaimed water requires stringent disinfection but inevitably generates disinfection by-products (DBPs). H2O2/O3 treatment is an efficient and environmentally benign disinfection method. For the first time, our bioassay results elucidate that low H2O2/O3 ratio (molar) treated water increased unignorable toxicity effect compared to that of the high H2O2/O3 ratio. To clarify this finding, individual organic brominated DBPs (Br-DBPs), bromate, and adsorbable organic bromine (AOBr) were considered due to their potential risk. Organic Br-DBPs were mainly generated from ozone-induced pathways. Individual organic Br-DBPs were not the primary concern in this scenario because they are typically only produced in observable quantities at bromide concentrations exceeding 500 μg/L, and even then, they often remain below detection limits when treated with H2O2/O3. On the contrary, both bromate and AOBr were detectable at low H2O2/O3 ratios. Furthermore, bromate is produced from HOBr and bromine radicals induced by HO•. Moreover, bromate formation was promoted because of increased HO• formation, particularly at H2O2/O3 ratios <0.24. To prevent HO•-induced pathways from being dominant, higher H2O2/O3 ratios (>0.48) were required. Toxicity assays revealed that AOBr-included organic extracts of ozonated reclaimed water induced more toxic effects. The toxicity induced by the organic fraction resulted from its decreased oxidation level, which was, in turn, driven by the increased formation of bromate. Enhanced toxicity effects were observed when cells were exposed to a bromate and organic extract mixture. It indicates that both the AOBr and bromate present in low-H2O2-O3-treated reclaimed water pose potential risks, and their coexistence further elevates these risks. Increasing the H2O2/O3 ratio markedly decreased the generation of intracellular oxidative substances and oxidative damage. In conclusion, when treated with H2O2/O3, shifting from HO•-induced pathways to ozone-induced pathways by a relatively high H2O2/O3 ratio decreased the amounts of DBPs produced and controlled the toxic effects to ensure the safety of ozonated reclaimed water.

Inflammation and Apoptosis-Related Damage in Lung, Liver, and Kidney Tissues due to Subarachnoidal Hemorrhage

Objective: Oxidant and inflammatory substances released into the blood due to subarachnoidal hemorrhage (SAH) can pass into the peripheral compartment, causing distant organ damage due to blood-brain barrier permeability caused by oxidative stress, inflammation, and apoptosis. This study aimed to demonstrate the secondary damage to peripheral organs, including the lung, kidney, and liver, resulting from SAH. Material and Method: Twenty rats were divided into sham and SAH groups, each consisting of ten animals. In the SAH group animals, 0.3 mL autologous blood taken from the tail artery was injected into the cisterna magna for 2 minutes. Seven days after SAH formation, all animals were euthanized under anesthesia. Following decapitation, brain tissues, lung, liver, and kidney tissues were placed in 10% formaldehyde for histopathological and immunohistochemical analysis. Results: In the SAH group, neuronal degeneration in the cerebral cortex, and hyperemia and hemorrhage in the lung, kidney, and liver were observed histopathologically. In immunohistochemical examinations, decreased expression of brain-derived neurotrophic factor (BDNF) and neurofilament (NF) in the cerebral cortex, cerebellum, and hippocampus sections; In lung tissues, enhanced caspase (Cas)-3, hypoxia-inducible factor 1 alpha (Hif-1α) and nuclear factor kappa beta (NF-κB) expressions in the lung, Cas-5, cyclooxygenase-1 (Cox-1) and interleukin (IL)-1 expressions in the liver, Cas-3, Cox-1 and IL-3 expressions in the kidney were observed. Conclusion: Following SAH, in addition to damage to brain tissue, peripheral tissues such as the lung, kidney, and liver can also be damaged through inflammation and apoptosis.

Molecular pathways of osmoregulation in response to salinity stress in the gills of the scalloped spiny lobster (Panulirus homarus) within survival salinity

Scalloped spiny lobster (Panulirus homarus) aquaculture is the preferred strategy to resolve the conflict between supply and demand for lobster. Environmental conditions, such as salinity, are key to the success of lobster aquaculture. However, physiological responses of P. homarus to salinity stress have not been well studied. This study investigated the gill histology, osmoregulation and gill transcriptome of the early juvenile P. homarus (weight 19.04 ± 3.95 g) cultured at salinity 28 (control), 18, and 38 for 6 weeks. The results showed that the gill filaments of P. homarus exposed to low salinity showed severe separation of the cuticle and epithelial cells due to water absorption and swelling, as well as the dissolution and thinning of the cuticle and the rupture of the septum that separates the afferent and efferent channels. The serum osmolarity of P. homarus varied proportionately with external medium salinity and remained consistently above ambient osmolarity. The serum Na+, Cl−, K+, and Mg2+ concentrations P. homarus exhibited a pattern similar to that of serum osmolality, while the concentration of Ca2+ remained unaffected at salinity 18 but significantly increased at salinity 38. Gill Na+/K+-ATPase activity of P. homarus increased (p < 0.05) under the both salinity stress. Salinity 18 significantly increased Glutamate dehydrogenase (GDH) and Glutamicpyruvic transaminase (GPT) activity in the hepatopancreas of P. homarus (p < 0.05). According to transcriptome analysis, versus control group (salinity 28), 929 and 1095 differentially expressed genes (DEGs) were obtained in the gills of P. homarus at salinity 18 and 38, respectively, with these DEGs were mainly involved in energy metabolism, transmembrane transport and oxidative stress and substance metabolism. In addition, the expression patterns of 8 key DEGs mainly related to amino acid metabolism, transmembrane transport and oxidative stress were verified by quantitative real-time PCR (RT-qPCR). The present study suggests that salinity 18 has a greater impact on P. homarus than salinity 38, and P. homarus demonstrates effective osmoregulation and handle with salinity fluctuations (18 to 38) through physiological and functional adaptations. This study provides an improved understanding of the physiological response strategies of P. homarus facing salinity stress, which is crucial for optimizing aquaculture practices for this species.

The potential treatment of N-acetylcysteine as an antioxidant in the radiation-induced heart disease.

Radiation-induced heart disease (RIHD) is a serious complication of thoracic tumor radiotherapy that substantially affects the quality of life of cancer patients. Oxidative stress plays a pivotal role in the occurrence and progression of RIHD, which prompted our investigation of an innovative approach for treating RIHD using antioxidant therapy. We used 8-week-old male Sprague-Dawley (SD) rats as experimental animals and H9C2 cells as experimental cells. N-acetylcysteine (NAC) was used as an antioxidant to treat H9C2 cells after X-ray irradiation in this study. In the present study, the extent of cardiomyocyte damage caused by X-ray exposure was determined, alterations in oxidation/antioxidation levels were assessed, and changes in the expression of genes related to mitochondria were examined. The degree of myocardial tissue and cell injury was also determined. Dihydroethidium (DHE) staining, reactive oxygen species (ROS) assays, and glutathione (GSH) and manganese superoxide dismutase (Mn-SOD) assays were used to assess cell oxidation/antioxidation. Flow cytometry was used to determine the mitochondrial membrane potential and mitochondrial permeability transition pore (mPTP) opening. High-throughput transcriptome sequencing and bioinformatics analysis were used to elucidate the expression of mitochondria-related genes in myocardial tissue induced by X-ray exposure. Polymerase chain reaction (PCR) was used to verify the expression of differentially expressed genes. X-ray irradiation damaged myocardial tissue and cells, resulting in an imbalance of oxidative and antioxidant substances and mitochondrial damage. NAC treatment increased cell counting kit-8 (CCK-8) levels (P=0.02) and decreased lactate dehydrogenase (LDH) release (P=0.02) in cardiomyocytes. It also reduced the level of ROS (P=0.002) and increased the levels of GSH (P=0.04) and Mn-SOD (P=0.01). The mitochondrial membrane potential was restored (P<0.001), and mPTP opening was inhibited (P<0.001). Transcriptome sequencing and subsequent validation analyses revealed a decrease in the expression of mitochondria-related genes in myocardial tissue induced by X-ray exposure, but antioxidant therapy did not reverse the related DNA damage. Antioxidants mitigated radiation-induced myocardial damage to a certain degree, but these agents did not reverse the associated DNA damage. These findings provide a new direction for future investigations by our research group, including exploring the treatment of RIHD-related DNA damage.

The influence mechanism of phospholipids structure and composition changes caused by oxidation on the formation of flavor substances in sturgeon caviar

The oxidation-induced phospholipids (PLs) underwent structural and compositional analysis, alongside the establishment of a simulation system to verify the link between phospholipid oxidation and flavor substances formation in sturgeon caviar. Structural alterations of PLs were tracked using 31P and 1H nuclear magnetic resonance (NMR), electron spin resonance spectroscopy (ESR), and Raman spectroscopy. The findings revealed a reduction in phosphatidylcholine (PC) and phosphatidylethanolamine (PE) from 82.3% and 10.4% to 58.2% and 5.8% respectively. Free radical signals exhibited an initial increase followed by a decrease. The diminished intensity in Raman spectra at 970 and 1080 cm−1 indicated reduced fat unsaturation attributable to PLs oxidation. Correlation analysis highlighted a significant association between PC and PE containing C22:6, C20:5, C20:4, and C18:2 with flavor substances, suggesting their role as key precursors for flavor development. This study established a theoretical basis for understanding the change of flavor quality in sturgeon caviar during storage.

A bifunctional protein RANbody based on nanobody facilitates dual-mode immunoassay of Staphylococcal enterotoxin B in food samples

Staphylococcal enterotoxin B (SEB), the major virulence factor of Staphylococcus aureus (S. aureus), brings about grievous food poisoning by infiltrating the food supply chain at diverse phases. ELISA based on traditional antibody and single signal analysis is slightly less specific and stable in SEB detection. Here, we innovatively reported an immunoassay based on a bifunctional protein reconstructed by nanobody, greatly enhancing the specificity of ELISA. Meanwhile, this is complemented by the second signal response, quenching effect of oxidative chromogenic substances on fluorochrome, to heighten the accuracy with dual mode. Under optimal conditions, the dual-mode immunoassay showed a wide linear range from 0.31 to 2500 ng/mL and a lower limit of detection (LOD) with 0.12 ng/mL for colorimetric mode and 0.24 ng/mL for fluorescence mode. There was no nonspecific binding occurred under the interference of S. aureus and other enterotoxins, demonstrating the splendid specificity. Moreover, the proposed assay was successfully employed in detecting SEB in food samples with satisfying practicability. This work integrated the nanobody modification technology with a dual signal sensing strategy, providing a reference for the development of a more specific and feasible platform for food safety.

Exploration of mitochondrial autophagy related genes in the diagnosis model construction and molecular marker mining of Alzheimer's disease based on multi-omics integration.

Key features of Alzheimer's disease include neuronal loss, accumulation of beta-amyloid plaques, and formation of neurofibrillary tangles. These changes are due in part to abnormal protein metabolism, particularly the accumulation of amyloid beta. Mitochondria are the energy production centers within cells and are also the main source of oxidative stress. In AD, mitochondrial function is impaired, leading to increased oxidative stress and the production of more reactive oxidative substances, further damaging cells. Mitophagy is an important mechanism for maintaining mitochondrial health, helping to clear damaged mitochondria, prevent the spread of oxidative stress, and reduce abnormal protein aggregation. To this end, this article conducts an integrated analysis based on DNA methylation and transcriptome data of AD. After taking the intersection of the genes where the differential methylation sites are located and the differential genes, machine learning methods were used to build an AD diagnostic model. This article screened five diagnostic genes ATG12, CSNK2A2, CSNK2B, MFN1 and PGAM5 and conducted experimental verification. The diagnostic genes discovered and the diagnostic model constructed in this article can provide reference for the development of clinical diagnostic models for AD.

Enhanced microbial remediation of uranium tailings through red soil utilization

Seepage of uranium tailings has become a focus of attention in the uranium mining and metallurgy industry, and in-situ microbial remediation is considered an effective way to treat uranium pollution. However, this method has the drawbacks of easy biomass loss and unstable remediation effect. To overcome these issues, spare red soil around the uranium mine was used to enhance the efficiency and stability of bioremediation. Furthermore, the bioremediation mechanism was revealed by employing XRD, FTIR, XPS, and 16S rRNA. The results showed that red soil, as a barrier material, had the adsorption potential of 8.21–148.00 mg U/kg soil, but the adsorption is accompanied by the release of certain acidic and oxidative substances. During the dynamic microbial remediation, red soil was used as a cover material to neutralize acidity, provide a higher reduction potential (<-200 mV), and increase the retention rate of microbial agent (19.06 mL/d) compared to the remediation group without red soil. In the presence of red soil, the anaerobic system could maintain the uranium concentration in the solution below 0.3 mg/L for more than 70 days. Moreover, the generation of new clay minerals driven by microorganisms was more conducive to the stability of uranium tailings. Through alcohol and amino acid metabolism of microorganisms, a reducing environment with reduced valence states of multiple elements (such as S2−, Fe2+, and U4+) was formed. At the same time, the relative abundance of functional microbial communities in uranium tailings improved in presence of red soil and Desulfovirobo, Desulfocapsa, Desulfosporosinus, and other active microbial communities reconstructed the anaerobic environment. The study provides a new two-in-one solution for treatment of uranium tailings and resource utilization of red soil through in-situ microbial remediation.

Efficient removal of fluoride from water: Adsorption performance of MgO-x adsorbents derived from Mg-MOF-74 and insights from DFT calculations

Magnesium oxide (MgO), an inexpensive and non-toxic substance, is considered an excellent and environmentally friendly fluoride adsorbent. In this study, a series of MgO-x materials (MgO-300, MgO-500, MgO-700 and MgO-800) were obtained by calcination with Mg-MOF-74 as a precursor, and they were used for efficient fluoride removal from wastewater. Both MgO-500 and MgO-700 exhibit excellent fluoride adsorption capacity in the pH range of 3.00–10.00. Specifically, their maximum adsorption capacities are 151.11 mg g−1 and 173.30 mg g−1, respectively. By analyzing the adsorption isotherm and kinetic data, it is confirmed that the adsorption of F− by MgO-x is more in line with the Langmuir isotherm model and the pseudo-second-order kinetic model. Interestingly, the adsorption rate of MgO-500 was significantly faster than that of MgO-700. MgO-x exhibited excellent repeat application performance, with MgO-500 maintaining 75.5 % fluoride ion removal efficiency and 81.5 % regeneration efficiency after five adsorption/desorption cycles. FTIR and XPS analyses show that the adsorption mechanism of fluorine on MgO-x is mainly the result of ligand exchange and electrostatic attraction. Density functional theory calculations show that the adsorption of fluorine on the MgO (110) plane is more favorable than on the (100) plane. This study demonstrates that magnesium oxide derived from Mg-MOF-74, as an economical and environmentally friendly material, has great potential to remove excess fluoride from water.

Glutamate rescues heat stress-induced apoptosis of Sertoli cells by enhancing the activity of antioxidant enzymes and activating the Trx1-Akt pathway in vitro

Heat stress reduces the number of Sertoli cells, which is closely related to an imbalanced redox status. Glutamate functions to maintain the equilibrium of redox homeostasis. However, the role of glutamate in heat treated Sertoli cells remains unclear. Herein, Sertoli cells from 3-week-old piglets were treated at 44 °C for 30 min (heat stress). Glutamate levels increased significantly following heat stress treatment, followed by a gradual decrease during recovery, while glutathione (GSH) showed a gradual increase. The addition of exogenous glutamate (700 μM) to Sertoli cells before heat stress significantly reduced the heat stress-induced apoptosis rate, mediated by enhanced levels of antioxidant substances (superoxide dismutase (SOD), total antioxidant capacity (TAC), and GSH) and reduced levels of oxidative substances (reactive oxygen species (ROS) and malondialdehyde (MDA)). Glutamate addition to Sertoli cells before heat stress upregulated the levels of glutamate-cysteine ligase, modifier subunit (Gclm), glutathione synthetase (Gss), thioredoxin (Trx1) and B-cell leukemia/lymphoma 2 (Bcl-2), and the ratio of phosphorylated Akt (protein kinase B)/total Akt. However, it decreased the levels of Bcl2-associated X protein (Bax) and cleaved-caspase 3. Addition of the inhibitor of glutaminase (Gls1), Bptes (Bis-2-(5-phenylacetamido-1,3,4-thiadiazol-2-yl)ethyl sulfide, 30 μM)to Sertoli cells before heat stress reversed these effects. These results inferred that glutamate rescued heat stress-induced apoptosis in Sertoli cells by enhancing activity of antioxidant enzymes and activating the Trx1-Akt pathway. Thus, glutamate supplementation might represent a novel strategy to alleviate the negative effect of heat stress.

Ferulic acid nanoemulsion as a promising anti-ulcer tool: in vitro and in vivo assessment

Objective Ferulic acid (FA) is a promising nutraceutical molecule which exhibits antioxidant and anti-inflammatory properties, but it suffers from poor solubility and bioavailability. In the presented study, FA nanoemulsions were prepared to potentiate the therapeutic efficacy of FA in prevention of gastric ulcer. Methods FA nanoemulsions were prepared, pharmaceutically characterized, and the selected nanoemusion was tested for its ulcer-ameliorative properties in rats after induction of gastric ulcer using ethanol, by examination of stomach tissues, assessment of serum IL-1β and TNF-α, assessment of nitric oxide, prostaglandin E2, glutathione, catalase and thiobarbituric acid reactive substance in stomach homogenates, as well as histological and immunohistochemical evaluation. Results Results revealed that the selected FA nanoemulsion showed a particle size of 90.43 nm, sustained release of FA for 8 h, and better in vitro anti-inflammatory properties than FA. Moreover, FA nanoemulsion exhibited significantly better anti-inflammatory and antioxidant properties in vivo, and the gastric tissue treated with FA nanoemulsion was comparable to the normal control upon histological and immunohistochemical evaluation. Conclusion Findings suggest that the prepared ferulic acid nanoemulsion is an ideal anti-ulcer system, which is worthy of further investigations.

Punicalagin attenuates isoproterenol-induced myocardial infarction through nuclear factor erythroid 2-related factor 2/silent information regulator transcript-1-mediated inhibition of inflammation and cardiac stress markers in experimental animal models.

Myocardial infarction (MI) is a significant global health issue and the leading cause of death. Myocardial infarction (MI) is characterized by events such as damage to heart cells and stress generated by inflammation. Punicalagin (PCN), a naturally occurring bioactive compound found in pomegranates, exhibits a diverse array of pharmacological effects against many disorders. This study aimed to assess the preventive impact of PCN, with its potential anti-inflammatory and antioxidant properties, on myocardial injury caused by isoproterenol (ISO) in rats and elucidate the possible underlying mechanisms. Experimental rats were randomly categorized into four groups: control group (fed a regular diet for 15 days), PCN group (orally administered PCN at 50 mg/kg body weight (b.w.) for 15 days), ISO group (subcutaneously administered ISO (85 mg/kg b.w.) on days 14 and 15 to induce MI), and PCN+ISO group (orally preadministered PCN (50 mg/kg b.w.) for 15 days and administered ISO (85 mg/kg b.w.) on days 14 and 15). The rat cardiac tissue was then investigated for cardiac marker, oxidative stress marker, and inflammatory marker expression levels. PCN prevented ISO-induced myocardial injury, suppressing the levels of creatine kinase-myocardial band, C-reactive protein, homocysteine, cardiac troponin T, and cardiac troponin I in the rats. Moreover, PCN treatment reversed (P<0.01) the ISO-induced increase in blood pressure, attenuated lipid peroxidation markers, and depleted both enzymatic and nonenzymatic markers in the rats. Additionally, PCN inhibited (P<0.01) ISO-induced overexpression of oxidative stress markers (p-38, p-c-Jun N-terminal kinase, and p-extracellular signal-regulated kinase 1), inflammatory markers (nuclear factor-kappa B, tumor necrosis factor-alpha, and interleukin-6), and matrix metalloproteinases and decreased the levels (P<0.01) of apoptosis proteins in the rats. Nuclear factor erythroid 2-related factor 2/silent information regulator transcript-1 (Nrf2/Sirt1) is a major cellular defense protein that regulates and scavenges oxidative toxic substances through apoptosis. Therefore, overexpression of Nrf2/Sirt1 to inhibit inflammation and oxidative stress is considered a novel target for preventing MI. PCN also significantly enhanced the expression of Nrf2/Sirt1 in ISO-induced rats. Histopathological analyses of cardiac tissue revealed that PCN treatment exhibited a protective effect on the heart tissue, mitigating damage. These findings show that by activating the Nrf2/Sirt1 pathway, PCN regulates oxidative stress, inflammation, and apoptosis, hence providing protection against ISO-induced myocardial ischemia.

Aucubin mitigates nonylphenol-induced renal damage by attenuating apoptosis, oxidative stress and histopathological profile

Nonylphenol (NP) is potent noxious pollutant which is documented to induce nephrotoxicity via escalating the levels of oxidative stress in renal tissues. Aucubin (AUC) is a novel phytochemical having tremendous pharmacological abilities. This research aimed to estimate the efficacy of AUC against NP intoxicated renal impairment in male albino rats. 48 albino rats were randomly assigned into four different groups viz. control group, NP administered group (50 mg/kg), NP + AUC administrated (50 mg/kg + 40 mg/kg) group and AUC treated (40 mg/kg) group. Our results showed that NP intoxication raised urinary proteins, creatinine, urea, urobilinogen, NGAL and KIM-1 levels. Besides, NP exposure lowered the levels of creatinine clearance and albumin. Furthermore, NP treatment lowered level of total protein, activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GSR) & glutathione (GSH) contents along with the level of total antioxidant status (TAS) however, raising the oxidative stress markers levels Thiobarbituric acid reactive substance (TBARS), reactive oxygen species (ROS), hydrogen peroxide (H2O2) & total oxidant status (TOS). Additionally, following the NP administration, the levels of Bax, caspase-9, & caspase-3 were augmented however the Bcl-2 level was decreased. Furthermore, rats exposed to NP showed various histopathological disruptions. Whereas treatment with AUC showed a palliative effect against NP-induced renal damage, restoring all alterations to normal levels. Taken together, AUC administration convalesced NP-induced kidney impairment.

WCx-Supported RuNi Single Atoms for Electrocatalytic Oxygen Evolution.

Single-atom catalysts anchored to oxide or carbonaceous substances are typically tightly coordinated by oxygen or heteroatoms, which certainly impact their electronic structure and coordination environment, thereby affecting their catalytic activity. In this study, we prepared a stable oxygen evolution reaction (OER) catalyst on tungsten carbide using a simple pyrolysis method. The unique structure of tungsten carbide allows the atomic RuNi catalytic site to weakly bond to the surface W and C atoms. XRD patterns and HRTEM images of the WCx-RuNi showed the characteristics of phase-pure WC and W2C, and the absence of nanoparticles. Combined with XPS, the atomic dispersion of Ru/Ni in the catalyst was confirmed. The catalyst exhibits excellent catalytic ability, with a low overpotential of 330 mV at 50 mA/cm2 in 1 m KOH solutions, and demonstrates high long-term stability. This high OER activity is ascribed to the synergistic action of metal Ru/Ni atoms with double monomers. The addition of Ni increases the state density of WCx-RuNi near the Fermi level, promoting the adsorption of oxygen-containing intermediates and enhancing electron exchange. The larger proximity of the d band center to the Fermi level suggests a strong interaction between the d electrons and the valence or conduction band, facilitating charge transfer. Our research offers a promising avenue for reasonable utilization of inexpensive and durable WCx carrier-supported metal single-atom catalysts for electrochemical catalysis.

Neuromodulation: Actions of Dopamine, Retinoic Acid, Nitric Oxide, and Other Substances on Retinal Horizontal Cells.

Whereas excitation and inhibition of neurons are well understood, it is clear that neuromodulatory influences on neurons and their synapses play a major role in shaping neural activity in the brain. Memory and learning, emotional and other complex behaviors, as well as cognitive disorders have all been related to neuromodulatory mechanisms. A number of neuroactive substances including monoamines such as dopamine and neuropeptides have been shown to act as neuromodulators, but other substances thought to play very different roles in the body and brain act as neuromodulators, such as retinoic acid. We still understandlittle about how neuromodulatory substances exert their effects, and the present review focuses on how two such substances, dopamine and retinoic acid, exert their effects. The emphasis is on the underlying neuromodulatory mechanisms down to the molecular level that allow the second order bipolar cells and the output neurons of the retina, the ganglion cells, to respond to differentenvironmental (ie lighting) conditions. The modulation described affects a simple circuit in the outer retina, involves several neuroactive substances and is surprisingly complex and not fully understood.

Alamandine attenuates oxidative stress in the right carotid following transverse aortic constriction in mice

ObjectivePressure overload can result in significant changes to the structure of blood vessels, a process known as vascular remodeling. High levels of tension can cause vascular inflammation, fibrosis, and structural alterations to the vascular wall. Prior research from our team has demonstrated that the oral administration of alamandine can promote vasculoprotective effects in mice aorta that have undergone transverse aortic constriction (TAC). Furthermore, changes in local hemodynamics can affect the right and left carotid arteries differently after TAC. Thus, in this study, we aimed to assess the effects of alamandine treatment on right carotid remodeling and the expression of oxidative stress-related substances induced by TAC. Methods and resultsMale C57BL/6 mice were categorized into three groups: Sham, TAC, and TAC treated with alamandine (TAC+ALA). Alamandine treatment was administered orally by gavage (30 µg/kg/day), starting three days before the surgery, and continuing for a period of fourteen days. Morphometric analysis of hematoxylin and eosin-stained sections revealed that TAC induced hypertrophic and positive remodeling in the right carotid artery. Picrosirius Red staining also demonstrated an increase in total collagen deposition in the right carotid artery due to TAC-induced vascular changes. Alamandine treatment effectively prevented the increase in reactive oxygen species production and depletion of nitric oxide levels, which were induced by TAC. Finally, alamandine treatment was also shown to prevent the increased expression of nuclear factor erythroid 2-related factor 2 and 3-nitrotyrosine that were induced by TAC. ConclusionOur results suggest that alamandine can effectively attenuate pathophysiological stress in the right carotid artery of animals subjected to TAC.