Prevention and treatment of lipoic acid-niacin on blue-light-induced retinal damage in rats / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the preventive effect and optimal drug dose of lipoic acid-niacin(N2L)against blue light-induced retinal damage in SD rats, and to explore its possible protective mechanism.METHODS: A total of 36 specific pathogen free-grade male SD rats of 150-200 g were selected and randomly divided into normal control group, blue light injury group, N2L low-dose group(1.0 mg/kg), N2L medium-dose group(2.5 mg/kg), N2L high-dose group(5.0 mg/kg), and physiological saline group, with 6 rats in each group. The normal control group was reared in a 12 h dark and light cycle, and the rest of the groups received 9 h of daily light exposure, 3 h of blue light irradiation with a wavelength of 455 nm and an intensity of 3000±50 lx, and 12 h of darkness to establish the injury model, and were exposed to light exposure for 14 d. For 14 consecutive durations, a 1 mL dose of the corresponding drug was injected intraperitoneally. The rats were reared for another 5 d with a regular 12 h light-dark cycle and were examined by electroretinography. Specimens were prepared by over anesthesia, HE staining, and the thickness of the outer nuclear layer was observed under a optical microscope; superoxide dismutases(SOD)activity was detected by CheKineTM SOD Activity Assay Kit; and the retinal Caspase-3, quinone oxidoreductase 1(NQO1), glutathione S transferase(GST), Bcl-2, and Bax protein expression in rat retina were detected by Western blot.RESULTS: The amplitude of b-wave in dark-vision ERG 3.0 and 10.0(cd·s)/m2 stimulated light, b-wave in bright-vision ERG 3.0(cd·s)/m2 stimulated light, and the amplitude of the 2nd wave peak of oscillatory potential were significantly lower in blue light injury group than that in the normal control group(all P<0.01), while the amplitude was significantly higher in the N2L medium-dose group than in the blue light injury group(all P<0.05), and was not statistically different from that of the normal control group; the thickness of the retina in the blue light injury group was decreased in the ONL compared with that of the normal control group(P<0.001), while in the N2L medium dose group, it was thicker than that of the blue light injury group(P<0.001), and there was no statistically significant difference from the normal control group; SOD activity was significantly higher in the N2L medium-dose group than in the remaining 5 groups(P<0.05); the expression of Caspase-3, Bax, and NQO1 in the blue light injury group was higher than that of the normal control group(all P<0.01), and expression of Bax and Caspase-3 was significantly lower in the N2L medium-dose group compared with the blue light injury group(all P<0.001), whereas GST, NQO1 and Bcl-2 were significantly increased(all P<0.01).CONCLUSION:A concentration of 2.5 mg/kg N2L can effectively antagonize the damaging effect of blue light on the retina of SD rats, and it is expected to be a preventive and curative drug for it.

The impact of COVID-19 on vitamin E concentrations and oxidative stress markers in adult subjects: A systematic review

Objective: To determine the impact of COVID-19 on vitamin E concentrations and oxidative stress in patients affected by the disease. Method: We conducted a systematic review using observational studies published between 2020 and 2023, which addressed the impact of COVID-19 on vitamin E concentrations and oxidative stress in patients affected by the disease. Review articles, clinical trials, letters to the editor, as well as studies conducted with pregnant women, animals and/or in vitro tests, and in languages other than English were excluded from this search. Studies were selected through a literature search in the following electronic databases: PubMed, Science Direct, and Web of Science, from October 2022 to May 2023. Results: Three articles were included in this review, consisting of patients with mild to severe symptoms, including those hospitalized in the intensive care unit. The reduction in vitamin E concentrations was in all studies accompanied by a reduction in enzymes involved in antioxidant action, such as superoxide dismutase, glutathione peroxidase, and glutathione reductase. In parallel to this, studies showed elevated concentrations of lipid peroxidation markers, such as malondialdehyde and myeloperoxidase. Conclusion: Infection with the SARS-COV-2 alters the activity of antioxidant cells and free radical defense agents.

Objetivo: Determinar el impacto del COVID-19 sobre las concentraciones de vitamina E y el estrés oxidativo en pacientes afectados por la enfermedad. Método: Se trata de una Revisión Sistemática, realizada mediante una prospección de estudios observatorios publicados entre 2020 y 2023, que abordaron el impacto de la COVID-19 sobre las concentraciones de vitamina E y el estrés oxidativo en pacientes afectados por la enfermedad. Se excluyeron de esta búsqueda artículos de revisión, ensayos clínicos, cartas al editor, así como estudios realizados con mujeres embarazadas, animales y/o ensayos in vitro, y en idiomas distintos al inglés. Los estudios se seleccionaron mediante una búsqueda bibliográfica en las siguientes bases de datos electrónicas: PubMed, Science Direct y Web of Science, desde octubre de 2022 hasta mayo de 2023. Resultados: Se incluyeron tres artículos en esta revisión, que consistían en pacientes con síntomas de leves a graves, incluidos los hospitalizados en la unidad de terapia intensiva. La reducción de las concentraciones de vitamina E se acompañó en todos los estudios de una reducción de las enzimas implicadas en la acción antioxidante, como la superóxido dismutasa, la glutatión peroxidasa y la glutatión reductasa. Paralelamente, los estudios mostraron concentraciones elevadas de marcadores de peroxidación lipídica, como el malondialdehído y la mieloperoxidasa. Conclusiones: La infección por el virus del SARS-CoV-2 altera la actividad de las células antioxidantes y de los agentes de defensa contra los radicales libres.

Effect of mobile phone radiofrequency electromagnetic radiations on oxidative stress and feeding behaviour in Sprague Dawley (SD) rats

Objectives: Radiofrequency electromagnetic radiation (RF-EMR) from mobile phones is known to produce a stress response because of its effect on hypothalamus. Mobile phones have become an integral part of our lives with increasing usage not only in terms of number of users but also increase in talk time. The present study aimed to study the effect of mobile phone radiofrequency electromagnetic radiations on oxidative stress and feeding behaviour assessment in Sprague Dawley (SD) rats. Materials and Methods: Twelve male SD rats of 10–12 weeks old, weighing 180–220 g, were housed and allowed to acclimatise in a room with 12:12 h light-dark cycle with ad libitum amount of food and reverse osmosis (RO) water before the start of the study. Then, rats were divided into control and RF-EMR exposed groups, and everyday feed intake and body weight were measured. At the end of the study period, blood sample was collected through retro orbital puncture for biochemical investigations. Results: The present study showed significant increase in malondialdehyde and serum corticosterone levels and decrease feeding behaviour in rats exposed to RF-EMR in rats exposed to RF-EMR. Conclusion: This study proves that mobile RF-EMR causes oxidative stress and oxidative damage leading to decreased feeding behaviour in SD rats.

Role and prospect of ferroptosis in ischemia-reperfusion injury during organ transplantation / 器官移植

Ferroptosis is a newly-emerged pattern of programmed cell death discovered in recent years, which is defined as iron-dependent programmed necrosis mediated by lipid peroxidation damage. As a conservative procedure, ferroptosis plays a vital role in the development and diseases of multiple organisms including plants and animals. Since ferroptosis was first reported in 2012, growing interests have been diverted to the process of ferroptosis and its role in disease treatment. Ischemia-reperfusion injury is a common pathological process during organ transplantation, and ferroptosis is considered as one of the main patterns inducing ischemia-reperfusion injury. Consequently, the definition, regulatory mechanism and the mechanisms of ferroptosis in ischemia-reperfusion injury after kidney, liver, heart and lung transplantations were reviewed, aiming to provide theoretical basis for the prevention and treatment of ischemia-reperfusion injury in organ transplantation.

Mechanisms mediating the inhibitory effects of quercetin against phthalates-induced testicular oxidative damage in rats / 南方医科大学学报

OBJECTIVE@#To explore the mechanism underlying the inhibitory effect of quercetin against testicular oxidative damage induced by a mixture of 3 commonly used phthalates (MPEs) in rats.@*METHODS@#Forty male Sprague-Dawley rats were randomly divided into control group, MPEs exposure group, and MPEs with low-, median- and high-dose quercetin treatment groups. For MPEs exposure, the rats were subjected to intragastric administration of MPEs at the daily dose of 900 mg/kg for 30 consecutive days; Quercetin treatments were administered in the same manner at the daily dose of 10, 30, and 90 mg/kg. After the treatments, serum levels of testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and testicular malondialdeyhde (MDA), catalase (CAT) and superoxide dismutase (SOD) were detected, and testicular pathologies of the rats were observed with HE staining. The expressions of nuclear factor-E2-related factor 2 (Nrf2), Kelch-like ECH2 associated protein 1 (Keap1) and heme oxygenase 1 (HO-1) in the testis were detected using immunofluorescence assay and Western blotting.@*RESULTS@#Compared with the control group, the rats with MPEs exposure showed significant reductions of the anogenital distance, weight of the testis and epididymis, and the coefficients of the testis and epididymis with lowered serum testosterone, LH and FSH levels (P < 0.05). Testicular histological examination revealed atrophy of the seminiferous tubules, spermatogenic arrest, and hyperplasia of the Leydig cells in MPEs-exposed rats. MPEs exposure also caused significant increments of testicular Nrf2, MDA, SOD, CAT and HO-1 expressions and lowered testicular Keap1 expression (P < 0.05). Treatment with quercetin at the median and high doses significantly ameliorated the pathological changes induced by MPEs exposure (P < 0.05).@*CONCLUSION@#Quercetin treatment inhibits MPEs-induced oxidative testicular damage in rats possibly by direct scavenging of free radicals to lower testicular oxidative stress and restore the regulation of the Nrf2 signaling pathway.

Isobaric tags for relative and absolute quantitation quantitative proteomics research of human lens epithelial cells after ultraviolet-B irradiation / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the changes of protein expressions in human lens epithelial cells(SRA01/04)undergoing oxidative damage, hoping to provide new protein target for the pathogenesis of age-related cataract(ARC).METHODS: SRA01/04 cells were divided into experimental group and control group. In the experimental group, cells were irradiated with ultraviolet-B(UVB)for 10min to establish the model of oxidative damage, whereas cells in the control group were untreated. Protein expression profile from the two groups was sequenced by isobaric tags for relative and absolute quantitation(iTRAQ). The filtering criteria that fold change &#x0026;#x003E;1.2 and p&#x0026;#x003C;0.05 was used to determine the differentially expressed proteins(DEPs). Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)database were utilized for functional enrichment analysis of the top 50 DEPs with either up-regulated or down-regulated significance. Furthermore, Pathway commons software was used to establish the protein-protein interaction(PPI)network.RESULTS: Overall, 552 DEPs were screened out. A total of 176 DEPs were up-regulated in the experimental group compared with the control group, including HMGB1 and USP1, while 376 DEPs were down-regulated, including POLR2A and POLR2B. GO and KEGG enrichment analysis indicated that the top 50 DEPs with up-regulated or down-regulated significance were involved in various crucial biological processes and signaling pathways. PPI network revealed that oxidative damage repair(ODR)-related proteins might play a key role in UVB-induced oxidative damage.CONCLUSIONS: The expressions of multiple proteins, especially ODR-related proteins, can be altered in SRA01/04 cells via UVB irradiation. These findings may provide cellular-related insights into the pathogenesis of ARC and into proteins or pathways associated with therapeutic targets.

Regulatory Mechanism of Berberine in Inhibiting Apoptosis and Autophagy in Ovarian Granulosa Cells Based on SIRT1/FoxO1 Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the protective effect and regulatory mechanism of berberine （BBR） against the senescence of ovarian granulosa cells. MethodA cell senescence model in the human ovarian granulosa-like tumor （KGN） cell line was induced by H2O2. A control group， a model group， and high-dose （1 μmol·L-1） and low-dose （0.5 μmol·L-1） BBR groups were set up. The cells in the model group and the BBR groups were incubated with 10 μmol·L-1 H2O2 for 40 min. The effect of BBR on KGN cell proliferation was detected by cell counting kit-8 （CCK-8） assay. The effect of BBR on the senescence of KGN cells was detected by β-galactosidase staining. The effects of BBR on the apoptosis and ROS content of KGN cells were detected by flow cytometry. The effects of BBR on the mRNA expression of B-cell lymphoma-2 （Bcl-2）/Bcl-2-associated X protein （Bax）， cysteinyl aspartate-specific protease-3 （Caspase-3）， forkhead transcription factor O1 （FoxO1）， and catalase （CAT） was detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. Western blot was used to detect the effects of BBR on protein expression of silent information regulator1 （SIRT1）， superoxide dismutase 2 （SOD2）， c-Jun N-terminal kinase （JNK）， FoxO1， autophagy-associated protein microtubule-associated protein light chain 3Ⅱ （LC3BⅡ）， mammalian ortholog of yeast Atg6 （Beclin-1）， and ubiquitin-binding protein p62. ResultAfter H2O2 induction for 40 min， the cell proliferation rate of the model group decreased compared with that of the control group （P<0.01）， and the cell proliferation rates of the BBR groups increased compared with that of the model group （P<0.05）. The results of β-galactosidase staining showed that the cells of the model group showed significant senescence compared with those of the control group （P<0.01）， and the cellular senescence in the BBR groups was reduced compared with that of the model group （P<0.01）. As revealed by flow cytometry， compared with the control group， the model group showed increased apoptosis rate （P<0.01）， and compared with the model group， BBR groups showed decreased apoptosis rates （P<0.05）. Meanwhile， the ROS content in the model group increased compared with that in the control group （P<0.01）， and compared with the model group， the BBR groups showed reduced cellular ROS content （P<0.01）. The Real-time PCR results showed that compared with the control group， the model group showed decreased mRNA expression of CAT and Bcl-2/Bax in KGN cells and increased mRNA expression of Caspase-3 and FoxO1 （P<0.05）， and compared with the model group， the BBR groups showed increased mRNA expression of CAT and Bcl-2/Bax （P<0.05） and reduced mRNA expression of Caspase-3 and FoxO1 in KGN cells （P<0.05）. As revealed by Western blot results， SIRT1， SOD2， and p62 protein levels decreased in the model group compared with those in the control group （P<0.01）， and JNK FoxO1， LC3BⅡ， and Beclin-1 protein levels increased （P<0.05）. After BBR intervention， SIRT1， SOD2， and p62 protein levels increased （P<0.01）， and JNK， FoxO1， LC3BⅡ， and Beclin-1 protein levels decreased compared with those in the model group （P<0.05）. ConclusionBBR has an inhibitory effect on ovarian granulosa cell senescence， and the mechanism is related to the inhibition of apoptosis and autophagy mediated by the SIRT1/FoxO1 pathway.

Meroterpenoids from Rhododendron nivale / 中国中药杂志

To elucidate the chemical material basis of Rhododendron nivale, this study comprehensively used various chromatographic techniques to isolate and obtain five new meroterpenoid enantiomers(1a/1b-5a/5b) from the ethyl acetate extract of R. nivale. A variety of spectral analytical methods, such as high-resolution mass spectrometry(HRMS), nuclear magnetic resonance spectroscopy(NMR), and infrared(IR) spectrum, were used to evaluate the structure, combined with the measurement and calculation of electronic circular dichroism(ECD). The new compounds 1a/1b-4a/4b were named as(±)-nivalones A-B(1a/1b-2a/2b) and(±)-nivalnoids C-D(3a/3b-4a/4b), along with one known enantiomer(±)-anthoponoid G(5a/5b). Human neuroblastoma cells(SH-SY5Y cells) induced by hydrogen peroxide(H_2O_2) were used as oxidative stress models to evaluate the protective activity of the isolated compounds against oxidative damage to nerve cells. It was found that compounds 2a and 3a had a certain protective effect on nerve cells against H_2O_2-induced oxidative damage at concentrations of 50 μmol·L~(-1), which increased the cell survival rate from 44.02%±2.30% to 67.82%±1.12% and 62.20%±1.87%, respectively. Other compounds did not show a significant ability to protect cells from oxidative damage. These findings enrich the chemical constituents of R. nivale and provide valuable information for identifying the structure of its meroterpenoids.

Biological effects and toxicity mechanisms of polystyrene nanoplastics: A review / 环境与职业医学

Polystyrene nanoplastics (PS-NPs) are widely used in industry, pharmaceutical and consumer packaging materials, and medical products. The biological health impacts of PS-NPs are receiving increasing attention. Therefore, it is necessary to conduct a literature review of in vitro and in vivo experimental studies from a biological mechanism perspective. Based on the latest research results at home and abroad, this review introduced the characteristics and cell internalization of PS-NPs in cytotoxicity experiments, and summarized the effects of PS-NPs on cytotoxic targets such as mitochondria, lysosomes, proteins, and DNA. In addition, the influencing factors of the health effects of PS-NPs were analyzed from the aspects of physical and chemical properties and cell types. Finally, by discussing the current research hotspots of cytotoxicity mechanism and biological effects, it was anticipated to provide a reference for the health risk management and biological safety assessment of PS-NPs.

A systematic review of hormone levels, biomarkers of cellular injury and oxidative stress in multi-stressor military field training exercises

ABSTRACT The fundamental objective of military field training exercises (FTX) is to prepare military personnel for real-life operations through simulated scenarios. These training sessions often require extreme physical efforts with prolonged, high-intensity exercises that can be combined with food restrictions and partial, or total, sleep deprivation. Such conditions can compromise an individual's physical performance and cause tissue damage, thus affecting their health. This study aimed to perform a systematic review of the literature to identify studies that measured the changes in hormone levels and biomarkers of cellular injury and oxidative stress resulting from FTX with high levels of energy expenditure combined with food and sleep restrictions. PubMed and the Scopus database were searched for articles that combined physical effort/food restriction/sleep deprivation with military training. The initial database search identified 158 articles that were reduced to 18 after confirmation. Significant reductions were reported in thyroid hormones, T3, T4, and anabolic hormones such as testosterone, insulin and androstenedione. An exception for GH was found, which increased throughout FTX. Less distinct responses to FTX were observed with cortisol, TSH and LH. The presence of biomarkers for cellular damage (myoglobin, TNF, and CRP) and increased immune response activities were also described. The scarcity of information on oxidative stress, analyses of cellular injury and biomarkers of inflammatory responses warrants the future study of these topics, which could be helpful in facilitating the safe and effective physical preparations of the members of the armed forces.

Establishment of lens opacity model in Grx2 knockout mice based on CRISPR/cas9 system and the role of Grx2 in the pathogenesis of cataract / 中华实验眼科杂志

Objective:To explore the role of Grx2 in the pathogenesis of cataract by establishing Grx2 knockout (KO) and knockin (KI) mouse models. Methods:Ten black C57BL/6J mice were selected to make Grx2 KO model ( n=5) and Grx2 KI model ( n=5) using CRISPR/Cas9 system.The offspring mice were sequenced by tail clipping and included in the corresponding experimental group according to the genotype.The general condition and lens opacity was recorded.After the mice were sacrificed, the pathological changes of lens were observed by hematoxylin-eosin staining.The contents of reactive oxygen species (ROS) and 8-hydroxy-desoxyguanosine (8-OHdG) were analyzed by enzyme-linked immunosorbent assay (ELISA).The relative expression levels of Grx2, glutathione (GSH), B-cell lymphoma-2 (Bcl-2) , glutathione disulfide (GSSG) and Bcl-2-associated X protein (Bax) in mice lens were assayed.The use and feeding of experimental animals were in accordance with the Regulations on the Management of Experimental Animals issued by the State Science and Technology Commission.The study protocol was approved by the Ethics Committee of the Second Affiliated Hospital of Chongqing Medical University (No.2020-125). Results:The offspring of Grx2 KO and Grx2 KI homozygous and heterozygous mice were confirmed by tail cutting nested PCR and gene sequencing.Compared with the wild type (WT) mice of same age, the lens opacity of Grx2 KO heterozygous mice occurred earlier, while the lens of Grx2 KI homozygous mice remained transparent all the time.A large number of gaps and vacuoles were found in the lens fibers of 5-month-old Grx2 KO mice.The 8-OHdG content and ROS fluorescence intensity in the lens of 5-month-old Grx2 KO mice were (3.886±0.326)ng/ml and 1 594±132, which were significantly higher than (3.531±0.250)ng/ml and 1 157±123 in WT mice ( t=2.711, P=0.033; t=3.384, P=0.028).The relative expression levels of Grx2, GSH and Bcl-2 in the lens of 5-month-old Grx2 KO mice were 0.23±0.01, 0.70±0.06 and 0.32±0.03, which were significantly lower than 0.52±0.02, 1.04±0.08 and 0.49±0.04 of WT mice ( t=2.815, P=0.020; t=2.457, P=0.033; t=2.279, P=0.041). Conclusions:Grx2 KO and Grx2 KI mouse models are successfully established in this study.The occurrence and development of age-related cataract are accelerated in Grx2 KO mice.

Mechanisms of ferroptosis in microglial cell line BV-2 cells after lead acetate exposure / 环境与职业医学

Background Lead exposure induces microglial cell death, of which the mechanism is unclear. Ferroptosis is a new death form and its role in microglia death has not been reported. Objective To investigate the role of ferroptosis in microglia following lead exposure in order to provide a theoretical basis for the mechanism of lead neurotoxicity. Methods Microglial cell line BV-2 cells were co-cultured with 0, 10, 20 and 40 μmol·L−1 lead acetate for 24 h. The 40 μmol·L−1 lead acetate group with iron chelator (DFO) was named the 40+DFO group. Changes in BV-2 cell morphology after lead exposure were observed under an inverted microscope; tissue iron kit and glutathione kit were used to detect intracellular iron and glutathione (GSH) respectively; flow cytometry was applied to detect lipid reactive oxygen species (lipid ROS) immunofluorescence intensity. Western blotting and qPCR were adopted to detect the expressions of glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), transferrin receptor 1 (TFR-1), divalent metal transporter 1 (DMT1), ferroportin 1 (FPN1) protein and mRNA. Results Compared with the control group, the number of BV-2 cells decreased with increasing doses of lead and the cells showed a large, round amoeboid shape. The intracellular levels of iron of BV-2 cells were (1.08±0.04), (1.29±0.03), and (1.72±0.10) mg·g−1 (calculated by protein, thereafter) in the 10, 20, and 40 μmol·L−1 lead acetate groups, respectively, significantly higher than that in the control group (P<0.05), and the intracellular level of iron in the 40+DFO group, (1.34±0.10) mg·g−1, was lower than that in the 40 μmol·L−1 lead acetate group, (1.72±0.03) mg·g−1 (P<0.05). Compared with the control group, the TFR-1 and DMT1 protein and mRNA expressions were increased in BV-2 cells in the 10, 20, 40 μmol·L−1 lead acetate groups (P<0.05), especially in the 40 μmol·L−1 lead acetate group; the FPN1 protein expression did not change significantly, but the FPN1 mRNA expressions in BV-2 cells in the 10, 20, 40 μmol·L−1 lead acetate groups were significantly decreased (P<0.05). Compared with the control group, the intracellular GSH level decreased and the lipid ROS content increased in all three lead acetate groups; compared with the 40 μmol·L−1 lead acetate group, the GSH level increased by 12.30% and the lipid ROS content decreased by 13.00% in the 40+DFO group (P<0.05). The expressions of GPX4 protein were reduced to 50.00%, 35.00%, and 17.00% of that of the control group in the 10, 20, and 40 μmol·L−1 lead acetate groups respectively, while the expressions of GPX4 mRNA were also significantly reduced; the expressions of SLC7A11 protein and mRNA in the 20 and 40 μmol·L−1 lead acetate groups were lower than that in the control group, with the most significant decrease in the 40 μmol·L−1 lead acetate group (P<0.05). Conclusion Lead exposure could induce ferroptosis in BV-2 cells, in which iron transport imbalance and oxidative damage might be involved.

Advances on association between indoor air pollution and 8-hydroxydeoxyguanosine in human urine / 环境与职业医学

8-hydroxydeoxyguanosine (8-OHdG) in human urine is a marker reflecting oxidative stress and DNA oxidative damage. People spend 80%-90% of their life indoors; therefore, indoor air quality is directly related to human health. In this paper, the urinary 8-OHdG levels were presented in populations grouped by different demographic characteristics, lifestyle, occupational exposure, and health status, and elucidated indoor pollutants affecting human urinary 8-OHdG level, such as pollutants from outdoor sources, smoking, indoor combustion and cooking fumes, the chemicals in interior decoration materials, and building foundation soils. The article aims to provide a theoretical basis for predicting the impact of indoor air pollution on human health (DNA oxidative damage and related diseases) by measuring the concentration of 8-OHdG in human urine.

Influence of Lycium barbarum Extract Intake on Oxidative Stress in Wistar Rats

Abstract: This study aimed to analyze the effects of Goji Berry extract (GB, Lycium barbarum) gavage administration on liver tissue oxidative stress in Wistar rats as well as to identify and quantify the content of the major bioactive compounds of the fruit. Four diets were applied: SW - standard diet + water; SG - standard diet + Goji Berry extract (125 mg/kg of animal); PW - palatable diet + water; PG - palatable diet + Goji Berry extract (125 mg/kg of animal). Results showed a significant increase in catalase enzyme activity in the liver of rats treated with GB and also in those intaking the palatable diet without GB when compared to the SW group. An increased mRNA expression of this enzyme in the same tissue and groups was also verified. Regarding lipid peroxidation, the GB extract produced a significant decrease in the oxidation state in the SG and PG groups. The results also showed a significant amount of bioactive compounds in GB extract.

Acutely applied melatonin prevents CCl4-induced testicular lesions in rats: the involvement of the oxidative capacity and arginine metabolism

Abstract Carbon tetrachloride (CCl4) represents an organic chemical that causes reactive oxygen species derived organ disturbances including male infertility. Melatonin (MLT) is a neurohormone with strong antioxidant capacity, involved in numerous physiological processes. In this study we evaluated the capability of MLT, administered in a single dose of 50 mg/kg, to preserve the testicular tissue function after an acute administration of CCl4 to rats. The disturbance in testicular tissue and the effects of MLT after CCl4 exposure were estimated using biochemical parameters that enabled us to determine the tissue (anti)oxidant status and the intensity of arginine/nitric oxide metabolism. Also, the serum levels of testosterone and the histopathological analysis of tissue gave us a better insight into the occurring changes. A significant diminution in tissue antioxidant defences, arginase activity and serum testosterone levels, followed by the increased production of nitric oxide and extensive lipid and protein oxidative damage, was observed in the CCl4-treated group. The application of MLT after the CCl4 caused changes, clearly visible at both biochemical and histological level, which could be interpreted mainly as a consequence of general antioxidant system stimulation and a radical scavenger. On the other hand, the application of MLT exerted a limited action on the nitric oxide signalling pathway.

Effect of exposure to low concentrations of benzene on miR-223 and miR-155 expression in peripheral blood lymphocytes / 预防医学

Objective @#To investigate the effect of exposure to low concentrations of benzene on miR-155 and miR-223 expression in peripheral blood lymphocytes among workers with benzene exposure. @*Methods @#A hundred male employees at a risk of exposure to benzene (the exposed group) were randomly sampled from two small metal products manufacturing enterprises and one medium-sized chemical raw material and chemical products manufacturing enterprise in Ningbo City, Zhejiang Province, and 60 age-matched male employees without benzene exposure were randomly selected as the unexposed group. Age, body mass index ( BMI ), smoking status, alcohol consumption, disease history, medication history and routine blood testing results of subjects were collected using a questionnaire survey. The 8-hour time weighted average concentration ( CTWA ) of benzene was measured in the workplace using thermal desorption gas chromatography, and the urine 8-hydroxy-2' deoxyguanosine ( 8-OHdG ) levels were determined using high-performance liquid-chromatography tandem mass spectrometry (HPLC-MS/MS). The miR-155 and miR-223 expression was quantified in peripheral blood lymphocytes using quantitative fluorescent reverse transcription-polymerase chain reaction assay, and the factors affecting miR-155 and miR-223 expression were identified using multivariable logistic regression analysis. @*Results @#The subjects in the exposed group had a mean age of ( 31.17±7.30 ) years, and were exposed to low concentrations of benzene ( CTWA, 0.05 to 0.30 mg/m3 ) , while the subjects in the unexposed group had a mean age of ( 32.52±6.15 ) years. There were no significant differences between the exposed and unexposed groups in terms of age, BMI, proportion of smokers or proportion of alcohol consumers ( P>0.05 ). There was no significant difference in the median relative miR-155 expression between the exposed and unexposed groups ( 0.953 vs. 1.293, P>0.05 ), and lower median relative miR-223 expression was quantified in the exposed group than in the unexposed group ( 0.540 vs. 1.433, P<0.05 ). Multivariable logistic regression analysis revealed that down-regulation of miR-223 expression correlated with exposure to benzene ( OR=2.719, 95%CI: 1.308-5.651 ). @*Conclusion @#Down-regulation of miR-223 expression may be associated with exposure to low concentrations of benzene.

Inhibitory effect of melatonin on pyroptosis of lens epithelium cells and its mechanism / 中华实验眼科杂志

Objective:To investigate the inhibitory effect of melatonin on pyroptosis of lens epithelium cells (HLECs) induced by hydrogen peroxide (H 2O 2) and its mechanism. Methods:The cultured HLECs were divided into normal control group, model control group, melatonin group, vitamin E group, and vitamin E solvent group.Cells in melatonin group, vitamin E group and vitamin E solvent group were pre-cultured with 1×10 -6 mol/L melatonin, 100 μmol/L vitamin E or equal volume of vitamin E solvent, then cultured with 100 μmol/L H 2O 2, respectively, and the cells in the normal control group and model control group were cultured with normal condition or 100 μmol/L H 2O 2, respectively.The HLECs transfected with nuclear factor erythroid 2-related factor 2 short hairpin RNA (shNrf2) or shNrf2 negtive control lentivirus and following with 100 μmol/L H 2O 2 treatment were served as shNrf2 group and shNrf2 negative control group, respectively; and the transfected cells treated with 1×10 -6 mol/L melatonin and subsequent 100 μmol/L H 2O 2 treatment were served as melatonin+ shNrf2 group and melatonin+ shNrf2 negative control group.The activity of lactic dehydrogenase (LDH) and the expression levels of interleukin (IL)-1β and IL-18 in the culture supernatant were detected by the enzyme linked immunosorbent assay (ELISA) kit.The concentration of reactive oxygen species (ROS) was assessed by flow cytometry.The expression level of Nrf2, NLRP3, apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC), caspase-1 p20 and GSDMD-N proteins were evaluated by Western blot. Results:Compared with model control group, the activity of LDH and the concentrations of IL-1β and IL-18 were significantly decreased in melatonin group and vitamin E group, showing statistically significant differences (all at P<0.05). The ROS fluorescence intensities were 13 040.67±1 550.66 and 12 593.67±1 677.06 in melatonin group and vitamin E group, respectively, which were significantly lower than 18 310.33±1 248.01 in model control group (both at P<0.05). The relative expression levels of Nrf2 protein were 4.24±0.44 and 3.73±0.38 in melatonin group and vitamin E group, respectively, which were significantly higher than 2.28±0.34 in model control group, and the relative expression levels of NLRP3, ASC, caspase-1 p20 and GSDMD-N in melatonin group and vitamin E group were significantly decreased than model control group (all at P<0.05). The relative expression level of Nrf2 protein in shNrf2 group and melatonin+ shNrf2 group was significantly reduced, and the expression levels of LDH, IL-1β, IL-18, ROS content, NLRP3, ASC, caspase-1 p20 and GSDMD-N were significantly increased in comparison with shNrf2 negative control group and melatonin+ shNrf2 negative control group, respectively (all at P<0.05). Conclusions:Melatonin can inhibit the release of NLRP3 inflammasome by activating Nrf2, and has an inhibitory effect on the pyroptosis of HLECs.

Effect of Buyang Huanwutang on Keap1/Nrf2/HO-1 Antioxidant Signaling Pathway in Rats with Idiopathic Pulmonary Fibrosis / 中国实验方剂学杂志

ObjectiveTo study the effect of Buyang Huanwutang on Kelch-like Ech-related protein 1 （Keap1）/nuclear factor E2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） antioxidant signaling pathway in rats with idiopathic pulmonary fibrosis （IPF） and explore the mechanism of this prescription in the treatment of IPF. MethodForty SPF-grade male SD rats were assigned into a sham operation group， a model group， a Buyang Huanwutang group， and a nintedanib group according to random number table method， with 10 rats in each group. IPF rat model was established by intratracheal infusion of bleomycin （0.005 g·kg-1） in other groups except the sham operation group. Buyang Huanwutang group was administrated with Buyang Huanwutang (14.84 g·kg-1)，intragastric administration of nitedanib suspension (0.1 g·kg-1)，sham operation group and model group were given equal volume of normal saline， for 28 days. After lung function test， serum and lung tissue samples were collected. Hematoxylin-eosin （HE） staining and Masson trichrome staining were employed to observe the pathological changes of the lung tissue. The content of hydroxyproline （HYP） in lung tissue was detected. The levels of malondialdehyde （MDA） in serum and lung tissue， and the activities of superoxide dismutase （SOD）， glutathione peroxidase （GSH-Px） and catalase （CAT） were determined. The mRNA and protein levels of Keap1， Nrf2， and HO-1 was determined by Real-time fluorescent quantitative polymerase chain reaction， immunohistochemical staining， and Western blot. ResultCompared with the sham operation group， the modeling increased the resistance and elasticity and decreased the compliance of respiratory system （P<0.01）， elevated the lung index， pathological score， and HYP content in lung tissue （P<0.01）， and enriched MDA in serum and lung tissue， while it decreased the activities of SOD， GSH-Px， and CAT （P<0.01）. Furthermore， the modeling down-regulated the mRNA and protein levels of Keap1 and up-regulated those of Nrf2 and HO-1 in lung tissue （P<0.01）. Compared with the model group， Buyang Huanwutang decreased the resistance and elasticity and increased the compliance of respiratory system （P<0.01）， lowered the lung index， pathological score， and HYP content in lung tissue （P<0.01）， and reduced MDA in serum and lung tissue， while it increased the activities of SOD， GSH-Px， and CAT （P<0.01）. Additionally， Buyang Huanwutang down-regulated the expression of Keap1 and up-regulated that of Nrf2 and HO-1 in lung tissue （P<0.05， P<0.01）. ConclusionBuyang Huanwutang can activate Keap1/Nrf2/HO-1 signaling pathway to enhance the antioxidant capacity and slow down the pathological process of IPF in rats.

Proteomics Analysis of Mechanism of Shenxiong Glucose Injection in Antagonizing H2O2-Induced Oxidative Damage in H9c2 Cells / 中国实验方剂学杂志

ObjectiveTo explore the mechanism of Shenxiong glucose injection （SGI） in inhibiting hydrogen peroxide （H2O2）-induced oxidative damage in H9c2 cells by tandem mass tags （TMT）-labeled quantitative proteomics. MethodH9c2 cells cultured in vitro were exposed to H2O2 for inducing oxidative damage. The cell viability was measured by cell proliferation and cytotoxicity assay （MTS）， followed by peptide fractionation by high performance liquid chromatography （HPLC） and protein expression detection in H9c2 cells by ultrahigh performance liquid chromatography-mass spectrometry. MaxQuant （v1.5.2.8） was utilized for data retrieval， and the high-resolution mass spectrometry was conducted to screen out differentially expressed proteins， which were then subjected to gene ontology （GO） and Kyoto encyclopedia of genes and genomes （KEGG） enrichment analysis. The protein expression levels of perilipin 2 （Plin2） and tropomyosin 1 （Tpm1） in cells were measured by Western blot. ResultThe spectral analysis yielded 48 608 specific peptide fragments and 5 903 quantifiable proteins. Compared with the model group，the SGI group exhibited 82 differentially expressed proteins，of which 22 were up-regulated and 60 were down-regulated. GO analysis results showed that the differentially expressed proteins were mainly involved in biological processes such as programmed cell death regulation，regulation of cell proliferation，cardiovascular system development， and cell migration. As revealed by KEGG analysis， these proteins were mainly related to peroxisome proliferator-activated receptor （PPAR），focal adhesion，phosphatidylinositol 3-kinase/protein kinase B（PI3K/Akt），and Ras-related protein 1 （Rap1） pathways. Western blot results demonstrated that compared with the model group，SGI significantly increased the Plin2 protein expression and decreased the Tpm1 protein expression （P<0.01），consistent with the proteomics results. ConclusionSGI may inhibit cell apoptosis and antagonize H2O2-induced cell oxidative damage by regulating PPAR，focal adhesion，PI3K/Akt and Rap1 pathways，which should be further verified by subsequent experiments.

Oxidative Damage to BV2 Cells by Trichloroacetic Acid: Protective Role of Boron via the p53 Pathway / 生物医学与环境科学（英文）

This study aimed to investigate the neurotoxicity induced by trichloroacetic acid (TCA) and the possible protective mechanisms of boron (B). Mouse BV2 cells were treated with TCA (0, 0.39, 0.78, 1.56, 3.12, 6.25, or 12.5 mmol/L) and B (0, 7.8, 15.6, 31.25, 62.5, 125, 500, or 1,000 mmol/L) for 3 h and 24 h, respectively. Then, reactive oxygen species, and supernatant proinflammatory cytokine and protein levels were analyzed after 24 h of combined exposure. Beyond the dose-dependent decrease in the cellular viability, it clearly increased after B supplementation ( P < 0.05). Moreover, B decreased oxidative damage, and significantly down-regulated IL-6 levels and up-regulated TNF-β production ( P < 0.05). B also decreased apoptosis via the p53 pathway. The present findings indicated that TCA may induce oxidative damage, whereas B mitigates these adverse effects by decreasing cell apoptosis.