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101.
《Bioorganic & medicinal chemistry letters》2019,29(16):2145-2149
Scavenging abilities of animal sera against six reactive species (OH, O2−, RO, t-BuOO, H3C, and 1O2) were determined with the use of multiple free-radical scavenging (MULTIS) method. Commercially available sera from pig, horse, rabbit, Guinea pig, hamster and chicken were subjected to MULTIS analysis and the results were compared with human specimen. In general, animal sera showed lower scavenging ability against OH and RO radicals than human serum. However, it is noteworthy that rabbit and chicken sera have higher scavenging ability against O2− than others. This is consistent with the known data that superoxide dismutase levels in these sera are high. In addition, we determined the uric acid level in animal sera using the uricase-TOOS method. In chicken serum, uric acid was found to be the major effective component in RO scavenging. This paper is first to quantitatively evaluate antioxidant capacities in animal sera. 相似文献
102.
David Charifson 《Invertebrate Biology》2019,138(4)
A laboratory experiment was conducted with the marine gastropod Littorina littorea from three different sites in Long Island Sound to test for inducible responses to the non‐native predatory crab Hemigrapsus sanguineus. Individuals of L. littorea did not exhibit decreased shell growth in response to increased predation risk, which differs from the response seen in other species of Littorina. However, snails did exhibit slower growth in response to reduced food availability, as seen in other gastropods. Surprisingly, snails from two sites exhibited differences between the crab‐exposed and reduced food‐availability treatments in how they remodeled the thickness of different microstructural layers of shell material in apical parts of the shell. Although individuals of L. littorea did not show the typical shell thickening response seen in other gastropods, they did show differences among populations in remodeling their shell. This underlies the importance of examining how the shell is constructed and remodeled in studies of inducible defenses in gastropods, as well as the importance of examining animals from multiple populations. 相似文献
103.
Two new acyl glycosides, angkorensides A and B (1 and 2) together with twelve known compounds including hedyotol C 7″-O-β-D-glucopyranoside (3), proanthocyanidin A-1 (4), (-)-epicatechin (5), (+)-lyoniresinol 3α-O-β-D-glucopyranoside (6), kaempferol-3-O-β-D-galactopyranoside (7), cuneataside E (8), 4-hydroxyacetophenone 4-O-(6′-O-β-D-apiofuranosyl)-β-D-glucopyranoside (9), cinnamtannin B-1 (10), aesculitannin B (11), quercetin 3-O-rham-(1−6)-β-D-galactopyranoside (12), quercetin 3-O-β-D-galactopyranoside (13), and proanthocyanidin A-2 (14) have been unprecedentedly isolated from Gardenia angkorensis Pit. Angkorensides A and B (1 and 2) showed moderate anti-inflammatory inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 macrophages and the known compounds (4, 10-14) exhibited strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. 相似文献
104.
The fruit of Actinidia arguta, also called kiwiberry or hardy kiwifruit has cold-resistant characteristics with diverse biological activities. In this study, investigations was carried out to characterize the bioactive constituents of A. arguta for the elucidation of its health beneficial properties. Three new succinate conjugated phenolic glycosides, namely argutinosides J–L (1-3) were isolated from the fruits of A. arguta. The structures were determined on the basis of combined spectroscopic analysis by IR, UV, HRESIMS, 1D and 2D NMR spectral analysis. Compounds 1 and 2 showed mild DPPH radical scavenging activity by 52.1 % and 68.2 %, respectively, at the concentration of 500 μM whereas compound 3 showed weak activity. 相似文献
105.
A bioassay-guided chemical investigation of the resin exudates from Daemonorops draco (dragon’s blood, Palmaceae) has resulted in the isolation of two new trinorditerpenes, 7β-13-dihydroxypodocarpa-8,11,13-trien-15-oic acid (1) and 7α-13-dihydroxypodocarpa-8,11,13-trien-15-oic acid (2), along with ten previously described abietane diterpenes, 7β-15-dihydroxydehydroabietic acid (3), 7α-15-dihydroxydehydroabietic acid (4), 15-hydroxydehydroabietic acid (5), 7-oxodehydroabietic acid (6), dehydroabietic acid (7), 15-hydroxyabietic acid (8), 12α-hydroxyabietic acid (9), abietic acid (10), 7,13,15-abietatrien-18-oic acid (11), and cephasinene B (12). The structures of 1 and 2 were elucidated using spectroscopic techniques, including HR-ESIMS and 1D/2D NMR. The absolute configurations were determined by comparing the experimental electronic circular dichroism (ECD) spectra with the calculated ECD data based on time-dependent density functional theory. The bioactivity of the extracts, fractions, and isolated compounds was assessed in oxidative stress-induced mesenchymal stromal cells (MSCs). The crude extract and the hexanes, ethyl acetate, and aqueous fractions exhibited high potency against oxidative stress-induced apoptosis of MSCs. Among the isolated compounds, compounds 1 (3 μM) and 10 (100 μM) demonstrated good recovery of MSCs against oxidative stress. 相似文献
106.
Fang Chen Hao Zhang Na Zhao Encun Du Feng Jin Qiwen Fan Wanzheng Guo Shaowen Huang Jintao Wei 《Animal : an international journal of animal bioscience》2022,16(6):100532
Magnolol and its isomer honokiol are polyphenols with anti-oxidative and anti-inflammatory activities. We evaluated the effects of magnolol and honokiol supplementation alone or in combination with hen diets during the late laying cycle. A total of 540 Jingfen pink-shell laying hens (50 weeks old) were randomly assigned to six treatments: a control diet and diets supplemented with 300 mg/kg magnolol (M300), honokiol (H300), or 300 mg/kg total phenols with a magnolol/honokiol ratio of 2:1 (M200H100), 1:2 (M100H200), and 1:1 (M150H150). Compared with that of the control, all supplementation groups had higher laying rates and the M300, M100H200, and M150H150 groups showed comparatively lower feed conversion ratios. Magnolol and honokiol supplementation increased the Haugh units of fresh eggs at week 62 and alleviated the decline of the Haugh units of eggs stored for 14 days. Compared with that of the control group, the serum total antioxidant capacity of the M100H200 and M150H150 groups significantly increased, and all supplementation groups had higher total antioxidant capacity and lower malondialdehyde content in the liver. With respect to lipid metabolism, the M200H100 and M150H150 groups had lower total and relative liver weights compared with those of the control and H300 groups. The mRNA expression levels of CCAAT enhancer binding protein alpha, sterol regulatory element binding protein-1, fatty acid synthase and stearyl coenzyme A desaturase 1 involved in lipogenesis; microsomal triglyceride transfer protein and apolipoprotein B involved in fatty acid transport; and the proinflammatory cytokine interleukin-1 beta were lower in all supplementation groups compared with those in the control. With respect to gut health, the heights of the jejunum and ileum villi significantly increased in all supplementation groups compared with those of the control, and the jejunum villus heights of the M300 and M150H150 groups were higher than those of the H300 and M100H200 groups. The H300 and M150H150 groups had higher mRNA expression levels of zonula occludens-1 in the ileum compared with those in the control and M300 groups, whereas all supplementation groups had higher mRNA levels of claudin-1 than that of the control group. In conclusion, magnolol and honokiol improved hen performance and the albumen quality of fresh and stored eggs by improving the antioxidant capacity, liver lipid metabolism, and intestinal health of laying hens. The combination of magnolol and honokiol at a 1:1 ratio may be an optimal choice for hen diet supplementation. 相似文献
107.
A large number of studies indicate that oxidative modification of plasma lipoproteins, especially low-density lipoprotein (LDL), is a critical factor in initiation and progression of atherosclerosis. We have previously found that ibuprofen (IBP), a potential antioxidant drug to inhibit LDL oxidation, interacted with lipoproteins in intact human plasma. In the present study, we compare the binding affinities of IBP to LDL and HDL (high-density lipoprotein) by (1)H NMR spectroscopy. When IBP is added into the HDL and LDL samples, the - N(+)(CH(3))(3) moieties of phosphatidylcholine (PC) and sphingomyelin (SM) in lipoprotein particles experience the chemical shift up-field drift. Intermolecular cross-peaks observed in NOESY spectra imply that there are direct interactions between ibuprofen and lipoproteins at both hydrophobic and hydrophilic (ionic) regions. These interactions are likely to be important in the solubility of ibuprofen into lipoprotein particles. Ibuprofen has higher impact on the PC and SM head group ( - N(+)(CH(3))(3)) and - (CH(2))(n) - group in HDL than that in LDL. This could be explained by either IBP has higher binding affinity to HDL than to LDL, or IBP induces orientation of the phospholipid head group at the surface of the lipoprotein particles. 相似文献
108.
Biochemical markers of oxidative stress in Perna viridis exposed to mercury and temperature 总被引:4,自引:0,他引:4
Oxidative damage and antioxidant properties have been studied in Perna viridis subjected to short-term exposure to Hg along with temperature (72h) and long-term temperature exposures (14 days) as pollution biomarkers. The elevated thiobarbituric acid reactive substances (TBA-RS) levels observed in gills and digestive gland under exposure to Hg, individually and combined with temperature, as also long-term temperature stress have been assigned to the oxidative damage resulting in lipid peroxidation (LPX). Increased activities of antioxidants such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR) and glutathione-S-transferase (GST) both in gills and digestive glands under long-term exposures to temperatures are more prominent to heat rather than cold stress suggesting activation of physiological mechanism to scavenge the ROS produced during heat stress. Also decreased values of reduced glutathione (GSH) on long exposures to temperature stress indicate utilisation of this antioxidant, either to scavenge oxiradicals or act in combination with other enzymes, was more than its production capacity under heat stress. The results suggest that temperature variation does alter the active oxygen metabolism by modulating antioxidant enzyme activities, which can be used as biomarker to detect sublethal effects of pollution. 相似文献
109.
Siddique HR Gupta SC Mitra K Murthy RC Saxena DK Chowdhuri DK 《Chemico-biological interactions》2007,169(3):171-188
The study was aimed to investigate the effect of leachates of solid waste from a flashlight battery factory and a pigment plant on 70 kDa heat shock protein (Hsp70) expression, generation of reactive oxygen species (ROS), antioxidant enzymes activities and apoptosis in Drosophila. Third instar larvae of Drosophila melanogaster transgenic for hsp70 (hsp70-lacZ) were fed on diet mixed with leachates of solid wastes (0.05-2.0%, v/v) released from two industrial plants at three different pHs (7.00, 4.93 and 2.88) for 2-48 h. A concentration- and time-dependent significant change in Hsp70 expression, ROS generation, antioxidant enzymes activities and MDA content was observed in the exposed larvae preceding the antioxidant enzymes activities. Mitochondria-mediated, caspase-dependent apoptotic cell death in the larvae exposed to 1.0 and 2.0% leachates of flashlight battery factory was concurrent with a significant regression in Hsp70 expression and a higher ROS generation. A positive correlation drawn between ROS generation and apoptotic markers and a negative correlation between apoptotic markers and Hsp70 expression in these groups indicated the important role of ROS in the leachate-induced cellular damage. Hsp70 along with antioxidant enzymes offered protection to the organisms exposed to all the tested concentrations of the leachates of pigment plant waste and 0.5% leachate of flashlight battery factory in a cooperative manner when ROS generation was less induced. Conversely, higher levels of ROS generation in the organisms treated with 1.0 and 2.0% leachate of flashlight battery factory after 24 and 48 h resulted in regression of Hsp70 expression in them leading to cell death. The study suggests that (1) leachates of flashlight battery factory waste more adversely affected the organisms in comparison to the leachates of pigment plant waste. (2) Hsp70 may be used as a biomarker of cellular damage in organisms exposed to leachates. (3) Cell based assays using D. melanogaster as an in vivo model may provide important mechanistic information about the adverse effect of xenobiotics. 相似文献
110.
Rajesh Kumar Tewari Soo Yeon Lee Eun Joo Hahn Kee Yoeup Paek 《Plant biotechnology reports》2007,1(4):227-235
Nitric oxide (NO) is a diffusible, gaseous signaling molecule. In plants, NO influences growth and development, and it can
also affect plant responses to various stresses. Because NO induces root differentiation and interacts with reactive oxygen
species, we examined the temporal effect of NO elicitation on root growth, saponin accumulation and antioxidant defense responses
in the adventitious roots of mountain ginseng (Panax ginseng). The observations revealed that NO is involved in root growth and saponin production. Elicitation with sodium nitroprusside
(SNP) activated O2
−-generating NADPH oxidase (NOX) activity, which most probably subsequently enhanced growth of adventitious roots of mountain
ginseng. A severe inhibition of NOX activity and decline in dry weight of SNP elicited adventitious roots in the presence
of NOX inhibitor (diphenyl iodonium, DPI), which further supports involvement of NOX in root growth. Enhanced activities of
antioxidant enzymes by SNP appear to be responsible for low H2O2, less lipid peroxidation, and modulation of ascorbate and non-protein thiol statuses in the adventitious roots of mountain
ginseng. Dry mass, saponin content and NOX activity was related with NO content present in adventitious roots of mountain
ginseng. 相似文献