We investigated the protective effects of 3-bromo-4,5-dihydroxybenzaldehyde (BDB) from Polysiphonia morrowii Harvey against hydrogen peroxide ($H_2O_2$)-induced apoptosis in Vero cells. BDB exhibited scavenging activity for DPPH, hydroxyl, and alkyl radicals. BDB also inhibited $H_2O_2$-induced lipid peroxidation, cell death, and apoptosis in Vero cells by inhibiting the production of ROS. To evaluate the molecular mechanisms of apoptosis inhibition, the expression of Bax/Bcl-xL and $NF-{\kappa}B$ was assessed by western blot assay. BDB significantly suppressed the cleavage of caspase-9 and PARP and reduced Bax levels in $H_2O_2$-induced Vero cells. Besides, BDB suppressed the phosphorylation of $NF-{\kappa}$B and the translocation of p65 in $H_2O_2$-induced cells. Furthermore, we evaluated the effect of BDB on ROS production, cell death, and lipid peroxidation in an $H_2O_2$-stimulated zebrafish embryo model. Taken together, these results indicated that ROS generation and cell death were significantly inhibited by BDB in zebrafish embryos, thereby proving that BDB exerts excellent antioxidant activity in vitro and in vivo.
In this study, the ion-gelation method was applied to fabricate novel Fe-carbon-bentonite-alginate beads ($Fe^0$/C-BABs). $Fe^0$/C-BABs could effectively control Fe release during persulfate (PS) activation in N-acetyl-p-aminophenol (APAP) oxidation. A novel two-stage approach that combined $Fe^0$/C-BABs and an oyster-shell-filled bed (OSFB) column was developed to address the low pH and high Fe concentration of the effluent of the traditional PS process. The application of the $Fe^0$/C-BABs and OSFB column regulated pH levels and Fe release during the advanced oxidation of APAP. The characteristics of $Fe^0$/C-BABs were also investigated through scanning electron microscopy, energy dispersive spectrometry, and Fourier transform infrared spectroscopy. The long-term operation performance of $Fe^0$/C-BABs in a continuous fixed-bed reactor under simultaneous PS and APAP feeding was also evaluated. The effects of initial PS concentration, pH, fixed-bed weight, in-flow rate, and dissolved oxygen (DO) were investigated. Under selected conditions, 86.3% efficiency was achieved during the first stage of APAP degradation (effluent pH of 3.05, Fe contents: $106.25mgL^{-1}$). Water quality improved after the effluent was passed through the OSFB column (effluent pH of 6.32, Fe contents: $21.43mgL^{-1}$). Moreover, this study analyzed the free radicals and intermediates produced during APAP degradation to identify the possible routes of APAP degradation.
Chang, Bo Yoon;Bae, Jin Hye;Kim, Da Eun;Kim, Dae Sung;Cho, Hyoung Kwon;Kim, Sung Yeon
Korean Journal of Pharmacognosy
/
v.51
no.4
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pp.278-290
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2020
The purpose of this study is to investigate the hangover relieving effect of HO-series. HO-S1 is an herbal mixture, which consists of extracts from Flower of Pueraria lobata Ohwi, Glycyrrhiza glabra Linné, Fruit of Lycium chinense Miller, Poria cocos Wolf, Acanthopanax sessiliflorum Seeman, Scutellaria baicalensis Georgi, Atractylodes lancea De Candlle and Zingiber officinale Roscoe. HO-S2 is a candidate that has been performed to ultra filtration based on HO-S1. HO-S3 is a mixture of amino acids and vitamins based on HO-S2. HO-01 is the final beverage base produced based on HO-S3. The antioxidant activity of HO-series was similar to that of vitamin C or trolox. The production of t-BHP induced reactive oxygen species(ROS) was significantly blocked in the presence of HO-series. In vivo study, AUC of alcohol and acetaldehyde concentrations in HO-S2 and HO-S3 treated groups significantly decreased. Hepatic alcohol dehydrogenase(ADH) and acetaldehyde dehydrogenase(ALDH) activity were significantly higher in HO-S2 and HO-S3 treated groups. And 2E1 activity and glutathione were significantly elevated, while the malondialdehyde level was not significantly in liver tissue. After alcohol exposure, the sensitivity scores of blood alcohol and acetaldehyde concentration and hangover symptoms were significantly decreased in the HO-01 intake group compared with the non-intake group. ALDH activity was significantly increased in the HO-01 intake group. HO-series have antioxidant activity and a protective effect from ROS. HO-S2, HO-S3 and HO-01 are potentially highly beneficial in relieving hangover, as it scavenges reactive free radicals and boosts the endogenous antioxidant system.
Lipopolysaccharide (LPS) is an endotoxin factor present in the cell wall of Gram-negative bacteria and induces various immune responses to infection. Recent studies have reported that LPS induces cellular stress in various cells including oocytes and embryos. Melatonin (N-acetyl-5-methoxytryptamine) is a regulatory hormone of circadian rhythm and a powerful antioxidant. It has been known that melatonin has an effective function in scavenging oxygen free radicals and has been used as an antioxidant to reduce the cytotoxic effects induced by LPS. However, the effect of melatonin on LPS treated early embryonic development has not yet been confirmed. In this study, we cultured mouse embryos in medium supplemented with LPS or/and melatonin up to the blastocyst stage in vitro and then evaluated the developmental rate. As a result of the LPS-treatment, the rate of blastocyst development was significantly reduced compared to the control group in all the LPS groups. Next, in the melatonin only treated group, there was no statistical difference in embryonic development and no toxic effects were observed. And then we found that the treatment of melatonin improved the rates of compaction and blastocyst development of LPS-treated embryos. In addition, we showed that melatonin treatment decreased ROS levels compared to the LPS only treated group. In conclusion, we demonstrated the protective effect of melatonin on the embryonic developmental rate reduced by LPS. These results suggest a direction to improve reproduction loss that may occur due to LPS exposure and bacterial infection through the using of melatonin during in vitro culture.
Objectives : Advanced glycation end product (AGEs) is combine formation of glucose and protein. AGEs and reactive oxygen species are potential therapeutic targets for the various disease such as diabetic complications, renal injury, skin damage. The aim of this study was investigated the AGEs inhibitory activity and antioxidant activity of water extracts from 40 Korean medicines and 5 heating-processed Korean medicines. Methods: AGEs formation inhibitory activities of Korean medicines measured using bovine serum albumin (BSA), glucose, and fructose. Then, five effective Korean medicines were selected and heated with 30% ethanol. The AGEs inhibitory activities of heated Korean medicine were measured compared with not-heated Korean medicines. The antioxidant activities were evaluated through radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals. Furthermore, we examined total phenol and flavonoids contents. Results: Scutellariae Radix, Corni Fructus, Persimmon Fruit, Paeoniae Radix, Mori Folium respectively reduced AGEs production. Morever, heating-processed Scutellariae Radix has AGEs inhibitory activities better than not-processed Scutellariae Radix. Heating- processed Scutellariae Radix scavenged DPPH and ABTS effectively and $IC_{50}$ of DPPH and ABTS radical scavenging activity of Heat processed Scutellariae Radix were $15.47{\pm}0.26{\mu}g/m{\ell}$ and $12.07{\pm}1.23{\mu}g/m{\ell}$. It caused heat processing methods of Scutellariae Radix up regulated total phenol and flavonoids contents ($26.68{\pm}0.01$ to $46.15{\pm}0.10$, $20.30{\pm}0.38$ to $64.20{\pm}0.52$). Conclusion: It has AGEs inhibitory activities that 20 kind of medicinal plants of 40 medicinal plants. Especially, heat processed Scutellariae Radix has excellent AGEs inhibitory activities and antioxidant effect.
Background: Panax notoginseng saponins (PNS) are bioactive substances extracted from P. notoginseng that are widely used to treat cardiovascular and cerebrovascular diseases and interstitial diseases. PNS have the functions of scavenging free radicals, anti-inflammation, improving blood supply for tissue and so on. Objectives: The aim of this study was to investigate the effects of PNS on the oxidative stress of immune cells induced by porcine circovirus 2 (PCV2) infection in vitro and in vivo. Methods: Using an oxidative stress model of PCV2 infection in a porcine lung cell line (3D4/2 cells) and mice, the levels of nitric oxide (NO), reactive oxygen species (ROS), total glutathione (T-GSH), reduced glutathione (GSH), and oxidized glutathione (GSSG) and the activities of xanthine oxidase (XOD), myeloperoxidase (MPO) and inducible nitric oxide synthetase (iNOS) were determined to evaluate the regulatory effects of PNS on oxidative stress. Results: PNS treatment significantly reduced the levels of NO and ROS, the content of GSSG and the activities of XOD, MPO, and iNOS (p < 0.05), while significantly increasing GSH and the ratio of GSH/GSSG in infected 3D4/2 cells (p < 0.05).Similarly, in the in vivo study, PNS treatment significantly decreased the level of ROS in spleen lymphocytes of infected mice (p < 0.05), increased the levels of GSH and T-GSH (p < 0.05), significantly decreased the GSSG level (p < 0.05), and decreased the activities of XOD, MPO, and iNOS. Conclusions: PNS could regulate the oxidative stress of immune cells induced by PCV2 infection in vitro and in vivo.
Proceedings of the Korean Society of Crop Science Conference
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2022.10a
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pp.197-197
/
2022
Wheat is highly susceptible to heat stress, which significantly reduces grain yield. In this study, we used RNA-seq technology to analyze the transcript expression at three different time-points after heat treatment in three cultivars differing in their susceptibility to heat stress: Jopum, Keumkang, and Olgeuru. A total of 11,751, 8850, and 14,711; 10,959,7946, and 14,205; and 22,895,13,060, and 19,408 differentially-expressed genes (log2 fold-change > 1 and FDR (padj) < 0.05) were identified in Jopum, Keumkang, and Olgeuru in the control vs. 6-h, in the control vs. 12-h, and in the 6-h vs. 12-h heat treatment, respectively. Functional enrichment analysis showed that the biological processes for DEGs, such as the cellular response to heat and oxidative stress-and including the removal of superoxide radicals and the positive regulation of superoxide dismutase activity-were significantly enriched among the three comparisons in all three cultivars. Furthermore, we investigated the differential expression patterns of reactive oxygen species (ROS)-scavenging enzymes, heat shock proteins, and heat-stress transcription factors using qRT-PCR to confirm the differences in gene expression among the three varieties under heat stress. This study contributes to a better understanding of the wheat heat-stress response at the early growth stage and the varietal differences in heat tolerancea.
So-Yeon Han;Tae-Won Jang;Da-Yoon Lee;Seo-Yoon Park;Woo-Jin Oh;Se Chul Hong;Jae-Ho Park
Proceedings of the Plant Resources Society of Korea Conference
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2023.04a
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pp.54-54
/
2023
Nypa fruticans Wurmb (N. fruticans) is a plant that belongs to Araceae and N. fruticans is mainly found in tropical mangrove systems. The parts (leaves, stems, and roots) of N. fruticans are traditionally used for asthma, sore throat, and liver disease. N. fruticans contains flavonoids and polyphenols, which are substances that have inhibitory effects on cancer and oxidant. In previous studies, some pharmaceutical effects of N. fruticans on melanogenesis and inflammation have been reported. The present study is conducted to investigate the effect of the ethyl acetate fraction of N. fruticans (ENF) on oxidative DNA damage and UVB-induced DNA damage. DNA damage response (DDR) pathway is important in research on cancer, apoptosis, and so on. DDR pathways are considered a crucial factor affecting the alleviation of cellular damage. ENF could reduce oxidative DNA damage derived from reactive oxygen species by the Fenton reaction. Also, ENF reduced the intensity of intracellular ROS in the live cell image by DCFDA assay. UVB is known to cause skin and cellular damage, then finally contribute to causing the formation of tumors. As for the strategies of reducing DNA damage by UVB, inhibition of p53, H2AX, and Chk2 can be important indexes to protect the human body from DNA damage. As a result of confirming the protective effect of ENF for UVB damage, MMPs significantly decreased, and the expression of apoptosis-related factors tended to decrease. In conclusion, ENF can provide protective effects against double-stranded DNA break (DSB) caused by oxidative DNA damage and UVB-induced DNA damage. These results are considered to be closely related to the protective effect against radicals based on catechin, epicatechin, and isoquercitrin contained in ENF. Based on these results, it is thought that additional mechanism studies for inhibiting cell damage are needed.
High soil salinity is the most severe threat to global rice production as it causes a significant decline in rice yield. Here, we investigated the effects of various plant extracts on rice plant stress associated with high salinity. Additionally, we examined various physiological and biochemical parameters such as growth, photosynthetic activity, chlorophyll content, and lipid peroxidation - in rice plants after treatment with selected plant extracts under salt stress conditions. Of the 11 extracts tested, four - soybean leaf, soybean stem, moringa (Moringa oleifera), and Undaria pinnatifida extracts - were found to effectively reduce salt stress. A reduction of only 3-23% in shoot fresh weight was observed in rice plants under salt stress that were treated with these extracts, compared to the 43% reduction observed in plants that were exposed to stress but not given plant extract treatments (control plants). The effectiveness varied with the concentration of the plant extracts. Water content was higher in rice plants treated with the extracts than in the control plants after 6 d of salt stress, but not after 4 d of salt stress. Although photosynthetic efficiency (Fv/Fm), electron transport rate (ETR), and the content of pigments (chlorophyll and carotenoid) varied based on the types and levels of stress and the extracts that the rice plants were treated with, generally, photosynthetic efficiency and pigment content were higher in the treated rice compared to control plants. Reactive oxygen species (ROS), such as superoxide radicals, hydrogen peroxide (H2O2), and malondialdehyde (MDA), increased as the duration of stress increased. ROS and MDA levels were lower in the treated rice than in the control plants. Proline and soluble sugar accumulation also increased with the duration of the stress period. However, proline and soluble sugar accumulation were lower in the treated rice than in the control plants. Generally, the values of all the parameters investigated in this study were similar, regardless of the plant extract used to treat the rice plants. Thus, the extracts found to be effective can be used to alleviate the adverse effects of stress on rice crops associated with high-salinity soils.
Oxidative stress by free radicals is a major cause of neuronal cell death. Excitotoxicity in hypoxia/ischemia causes an increase in reactive oxygen species (ROS) and a loss of mitochondrial membrane potential (MMP), resulting in dysfunction of the mitochondria and cell death. Pinelliae Rhizoma (PR) is a traditional medicine for incipient stroke. We investigated the effects of PR Water-Extract on the modulation of ROS and MMP in a hypoxic model using cultured rat cortical cells. PR Water-Extract was added to the culture medium at various concentrations (0.25${\sim}$5, 5.0 ${\mu}g/ml$) on day in vitro 12(DIV12), given a hypoxic shock (2% $O_2$/5% $CO_2$, $37^{\circ}C$, 3 hr), and cell viability was assessed on DIV15 by Lactate Dehydrogenase Assay (LDH assays). PR Water-Extract showed a statistically significant effect on neuroprotection (10${\sim}$15% increase in viability; p<0.01) at 1.0 and 2.5 ${\mu}g/ml$ in normoxia and hypoxia. Measurement of ROS production by $H_2DCF-DA$ stainings showed that PR Water-Extract efficiently reduced the number and intensity of ROS-producing neurons, especially at 1 hr post shock and DIV15. When MMP was measured by JC-1 stainings, PR Water-Extract efficiently maintained high-energy charged mitochondria. These results indicate that PR Water-Extract protects neurons in hypoxia by preventing ROS production and preserving the cellular energy level.
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