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1.
Lam PY  Yan CW  Chiu PY  Leung HY  Ko KM 《Fitoterapia》2011,82(3):393-400
Schisandrin B (Sch B) and schisandrin C (Sch C), but not schisandrin A and dimethyl diphenyl bicarboxylate, protected rat skin tissue against solar irradiation-induced oxidative injury, as evidenced by a reversal of solar irradiation-induced changes in cellular reduced glutathione and α-tocopherol levels, as well as antioxidant enzyme activities and malondialdehyde production. The cytochrome P-450-mediated metabolism of Sch B or Sch C caused ROS production in rat skin microsomes. Taken together, Sch B or Sch C, by virtue of its pro-oxidant action and the subsequent eliciting of a glutathione antioxidant response, may prevent photo-aging of skin.  相似文献   

2.
The effect of schisandrin B (Sch B) on long-term ethanol-induced oxidative stress in various rat tissues was investigated. Long-term ethanol treatment increased reactive oxygen metabolites (ROM) level in plasma. The ethanol-induced oxidative stress was assessed by mitochondrial glutathione and α-tocopherol levels, antioxidant enzyme activities, malondialdehyde (mtMDA) production and heat shock protein (Hsp) 25/70 levels. Liver was most susceptible to oxidative stress with a significant increase in mtMDA production. Long-term Sch B treatment enhanced mitochondrial antioxidant status in a tissue non-specific manner. Sch B co-treatment ameliorated the alterations in plasma ROM levels, mtMDA production and Hsp 25/70 expression in rat tissues.  相似文献   

3.
Acute kidney injury (AKI) is an abrupt loss of kidney function. Severe AKI requires renal replacement therapy and has high mortality. Leonurine (LEO), an alkaloid isolated from Leonurus cardiaca, has shown biological effects such as antioxidant, anticoagulant, and anti-apoptosis. We have examined the effect of LEO on lipopolysaccharide (LPS)-induced AKI in mice and further studied the mechanism involved. Blood urea nitrogen (BUN), creatinine and cytokine were estimated in the serum or tissue. Kidney tissue specimens were used for biochemical estimations of lipid peroxides (LPO), reduced glutathione (GSH), and reactive oxygen species (ROS). The effects of LEO on LPS-induced renal tissue damage were detected by hematoxylin and eosin (HE) stain and electron microscopy. The production of cytokines in the tissue and blood was measured by ELISA. Protein phosphorylation and protein subcellular localization were tested by Western blot. LEO is protected against LPS-induced AKI, improved animal survival and maintained the redox balance. The beneficial effects of LEO were accompanied by the down-regulation of TNF-α, IL-1, IL-6, IL-8, KIM-1 expression and by the inhibition of the phosphorylation of IκBα and p65 translocalization. These results suggest that LEO may suppress NF-κB activation and inhibit pro-inflammatory cytokine production via decreasing cellular ROS production. Accumulating studies have demonstrated that LEO reduces kidney injury and protects renal functions from LPS-induced kidney injury.  相似文献   

4.
本研究报道沙棘(胡颓子科)对雄性白化病白鼠由铬诱导氧化胁迫的抗氧化活性。氧化胁迫通过对小白鼠进行强制性喂养30 d,以浓度为30 m g/kg的铬相对体重比例的重铬酸钾盐实现。铬促使体重下降,而却明显增加了器官与体重比例。铬处理明显减少了谷胱甘肽的降低,增加了丙二醛和肌氨酸磷酸激酶的水平;而且它还加强了血清中谷氨酸草酰乙酸转移酶和谷氨酸丙酮酸转移酶的浓度。用不同剂量的沙棘叶子提取物(乙醇提取)对保护铬元素诱导的氧化胁迫进行了评估,结果表明叶子提取物在浓度为100到250 m g/kg铬与体重比的情况下可以明显保护动物避免由铬所诱导的氧化伤害。  相似文献   

5.
The cytoprotective effect of piperine on benzo[a]pyrene (B[a]P) induced experimental lung cancer was investigated in male Swiss albino mice. Oral administration of piperine (100 mg/kg body wt.) effectively suppressed lung cancer initiated with B[a]P as revealed by the decrease in the extent of lipid peroxidation with concomitant increase in the activities of enzymatic antioxidants (superoxide dismutase, catalase and glutathione peroxidase) and non-enzymatic antioxidant (reduced glutathione, vitamin E and vitamin C) levels when compared to lung cancer bearing animals. Our data suggest that piperine may extend its chemopreventive effect by modulating lipid peroxidation and augmenting antioxidant defense system.  相似文献   

6.
To estimate net ecosystem production (NEP), ecosystem respiration (R E), and gross primary production (GPP), and to elucidate the interannual variability of NEP in a cool temperate broadleaf deciduous forest in Sapporo, northern Japan, we measured net ecosystem exchange (NEE) using an eddy covariance technique with a closed-path infrared gas analyzer from 2000 to 2003. NEP, R E, and GPP were derived from NEE, and data gaps were filled using empirical regression models with meteorological variables such as photosynthetic active radiation and soil temperature. In general, NEP was positive (CO2 uptake) from May to September, either positive or negative in October, and negative (CO2 release) from November to the following April. NEP rapidly increased during leaf expansion in May and reached its maximum in June or July. The four-year averages (±?standard deviation) of annual NEP, GPP, and R E were 443?±?45, 1,374?±?39, and 931?±?11?g?C?m?2?year?1, respectively. The lower annual NEP and GPP in 2000 may have been caused by lower solar radiation in the foliated season. During the foliated season, monthly GPP varied from year to year more than monthly R E. Variations in the amount of incoming solar radiation may have caused the interannual variations in the monthly GPP. Additionally, in May, the timing of leaf expansion had a large impact on GPP. Variations in GPP affected the interannual variation in NEP at our site. Thus, interannual variation in NEP was affected by the incoming solar radiation and the timing of leaf expansion.  相似文献   

7.
Recent studies have shown that winter needle mortality in red spruce (Picea rubens Sarg.) is increased by exposure to direct solar radiation, possibly as a result of photo-oxidative damage, accelerated winter desiccation, or reduced cold tolerance due to heating of sun-exposed needles. In an experiment at controlled subfreezing air temperatures of -10 to -20 degrees C, visible radiation was less effective than infrared radiation in producing needle desiccation and visible injury during freeze-thaw cycles. However, visible radiation produced a red-brown color in injured needles, similar to natural winter injury, whereas injured needles exposed to infrared radiation were yellow and injured needles kept in darkness were dark brown. Thus, visible radiation was necessary to produce the red-brown color of damaged needles, but not the injury itself. Needle desiccation was not strongly correlated with visible injury, but the pattern of variation in visible injury among trees and the positive correlation between electrolyte leakage and visible injury suggested that freezing damage following freeze-thaw cycles might cause the visible injury. This was confirmed by a second experiment that showed loss of cold hardiness in needles thawed by radiational heating for six consecutive days. Even with a constant nighttime temperature of -10 degrees C, six days of radiational heating of needles to above freezing caused a small (2.8 degrees C) mean decrease in needle cold tolerance, as measured by electrolyte leakage. Continuous darkness at -10 degrees C for six days resulted in an estimated 5.6 degrees C mean increase in needle cold tolerance. Freezing injury stimulated desiccation: cooling at 4 degrees C h(-1) to -43 or -48 degrees C increased the dehydration rate of isolated shoots by a factor of two to three during the first day after thawing. Within three days at 15 to 22 degrees C and 50% relative humidity, the mean water content of these shoots fell to 60% or lower, compared to 90% or greater for unfrozen controls or shoots subject to less severe freezing stress. In some but not all severely freeze-stressed shoots, accelerated needle desiccation and abscission were accompanied by a red-brown color typical of red spruce winter needle injury. We conclude that severe winter desiccation in red spruce may often be due to prior freezing injury, increased as a result of exposure to direct solar radiation. Furthermore, freezing injury in red spruce may sometimes cause desiccation and abscission of green needles.  相似文献   

8.
Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) is cosmopolitan pest of stored products. The effect of strong magnetic fields (MFs) on DNA damage and oxidative stress on larvae stage of E. kuehniella was assessed. Antioxidant enzyme systems, which include superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), and malondialdehyde (MDA), the end product of lipid peroxidation as a result of strong MF intoxication that might occur in the larvae tissue, were evaluated. A simple technique of single-cell gel electrophoresis (DNA comet assay) enabled a quick detection of MF treatment on larvae. The larvae were exposed in a 1.4-Tesla (T) MF from a DC power supply at 50 Hz for different time periods (3, 6, 12, 24, 48, and 72 h). MFs caused increasing DNA damage and demonstrated using the comet assay with its parameters including tail DNA%, tail length and tail moment. DNA damage at increasing exposure times were significantly larger than the control group (p < 0.05). These parameters were detected using BS 200 ProP with image analysis software. SOD, CAT, GPx, and GST activities decreased and MDA level increased in the MF-treated group in larvae tissue compared to control group for increasing exposure times at 1.4 T (p < 0.05). In our investigation, we showed that MFs caused oxidative stress and proved to be DNA damage as revealed by the comet assay. MFs may be used to determine potential toxic effects as a control agent against E. kuehniella larvae.  相似文献   

9.
Acute exposure to ultraviolet (UV) radiation causes pro-inflammatory responses via diverse mechanisms including oxidative stress. Codium fragile is a green alga of Codiales family and has been reported to exhibit anti-edema, anti-allergic, anti-protozoal and anti-mycobacterial activities. In this study, we have investigated a novel anti-inflammatory potential of C. fragile using in vitro cell culture as well as in vivo animal models. In HaCaT cells, buthanol and ethylacetate fractions of 80% methanol C. fragile extract (CFB or CFE) and a single compound, clerosterol (CLS) isolated from CFE attenuated UVB (60 mJ/cm2)-induced cytotoxicity and reduced expression of pro-inflammatory proteins including cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and tumor necrosis factor-α (TNF- α). Moreover, CFB, CFE and CLS effectively suppressed UVB-induced production of pro-inflammatory mediators such as prostaglandin E2 (PGE2) and nitric oxide (NO). In another experiment, topical application of CFB, CFE or CLS prior to UVB irradiation (200 mJ/cm2) on BALB/c mice, inhibited the UVB-elevated protein levels of COX-2, iNOS, and TNF-α. Furthermore, CFB, CFE and CLS suppressed oxidative damages caused by UVB irradiation for example lipid peroxidation and/or protein carbonylation, which seemed to be mediated by up-regulation of antioxidant defense enzymes. These results suggest that C. fragile could be an effective therapeutic agent providing protection against UVB-induced inflammatory and oxidative skin damages.  相似文献   

10.
A herbal preparation “Compound Codyceps-TCM-700C (CC-700C)” was tested for hepatoprotective effect against the carbon tetrachloride induced liver damages in Sprague-Dawley rat model for a period of 6-weeks. Two dosage levels of CC-700C, respectively 286.2 mg/kg-bw (L-TCM) and 2862 mg/kg-bw (H-TCM), and a positive control Silymarin (Sigma) were used to compare their therapeutic effect. Both CC-700C's and Silymarin showed nontoxic in nature, as evidenced by body weight gain, organ weights and appearance including liver, spleen, and kidney. The activities of aspartate aminotransferase (AST) and alanine-aminotransferase (ALT) were more effectively suppressed by CC-700C than Silymarin. In addition, all levels of serum bilirubin, serum albumin, triglyceride (TG), total cholesterol (TC), platelet count (PLT), and prothombin time (PT) except TG were shown effectively restored to normal values by CC-700C and Silymarin. Moreover, although levels of glutathione (GSH), glutathione reductase (GSH-Rd), and superoxide dismutase (SOD) were equally maintained by these three preparations, glutathione peroxidase (GSH-Px) was suppressed only by H-TCM, and SOD only by Silymarin. In contrast, the activity of catalase efficiently recovered to control level on administration of CC-700C, being far better than Silymarin. Finally the liver collagen content, an indication of fibrosis, was also significantly suppressed by CC-700C, better effect was by L-TCM, but both levels were superior to Silymarin. Conclusively, the herbal preparation “Compound Cordyceps TCM-700C” is a potent hepatoprotective preparation. For therapeutic use, a dosage of 286.2 mg/kg-bw would be sufficiently effective.  相似文献   

11.
Oxidative damage is an established outcome of chronic stress. Thus, the present study was designed to investigate the modulatory role of ethanolic extract of Evolvulus alsinoides (EA) in terms of oxidative alterations at peripheral and central level in rats subjected to chronic unpredictable stress (CUS). CUS exposure for 7 days reduced Cu, Zn superoxide dismutase and catalase activity with increase in glutathione peroxidase activity and lipid peroxidation, while decrease in reduced glutathione level in blood plasma, frontal cortex and hippocampus regions of brain. Oral administration of EA extract at 200 mg/kg p.o. normalized these stress induced oxidative alterations with an efficacy similar to that of melatonin. Further, EA extract was taken up for detailed chemical investigation. Two new flavonol-4′-glycoside, kaempferol 4′-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (3) and kaempferol 4′-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside (5) were isolated, along with eight known compounds (1, 2, 4 and 6–10). The structures of new compounds were established by detailed spectroscopic studies, while known compounds were characterized by direct comparison of their reported NMR data. All these compounds were evaluated for their in vitro antioxidant activity. Compounds 3, 5, 9 and 10 at 100 and 200 μg/ml showed significant in vitro antioxidant activity. Therefore, EA may hold great potential in preventing clinical deterioration in stress induced oxidative load and related disorders.  相似文献   

12.
To assess the role of solar warming and associated temperature fluctuations in the winter injury of sun-exposed red spruce foliage, we used fine wire thermocouples to monitor midwinter needle temperature in the upper canopy of mature red spruce trees over two winters. In 1989-1990, 15-min mean temperatures were recorded for six needles in a single tree. In 1990-1991, 10-min mean temperatures of six needles in one tree, and 1-min mean temperatures of seven needles in a second tree were recorded during rapid temperature changes. Warming was more frequent and greatest on terminal shoots of branches with a south to southwest aspect. The maximum rise above ambient air temperature exceeded 20 degrees C, and the maximum one minute decrease in temperature was 9 degrees C, with maximum rates of 0.8 and 0.6 degrees C min(-1) sustained over 10- and 15-min intervals, respectively. These data demonstrate that red spruce is subject to rapid temperature fluctuations similar to those known to produce visible injury in American aborvitae, a much hardier species. We concluded that solar warming to temperatures above the freezing point was unlikely to result in dehardening and subsequent freezing injury, because warming was infrequent, of short duration, and did not always raise needle temperature above the freezing point. Parts of branches and some individual shoots were frequently covered by snow or rime that may have prevented injury by reducing the frequency or intensity of needle temperature fluctuations. Radiation load on exposed shoots may have been increased by reflection of short wave radiation from snow and rime deposits on surrounding surfaces, which would exacerbate temperature fluctuations.  相似文献   

13.
The methanol extracts of Astragalus plumosus var. krugianus Chamb. & Matthews afforded sixteen cycloartane glycosides among which krugianoside A, was never reported before. All compounds were evaluated for their cytotoxic activity in human skin fibroblast WS1 cells. For compounds exhibiting no significant effect on WS1 viability, the antioxidant potential was examined. Compounds 1 and 8 prevented elevation of ROS induced by t-BOOH, suggesting the potential activity of these compounds to protect fibroblasts from oxidative stress.  相似文献   

14.
An alkaloid with novel skeleton, sinoscrewtine (1), has been isolated from the roots of Sinomenium acutum. Its structure was established by spectral analysis and X-ray crystallographic study, and its possible biosynthetic pathway was delivered. In vitro experiments, 1 showed weak injurious effects against H2O2/Aβ25–35 induced oxidative injury in PC-12 cells and DPPH radical scavenging activity with IC50 of 32.6 μM.  相似文献   

15.
Anoectochilus roxburghii is a traditional Chinese herb used for the treatment of diabetes and some other diseases. The vascular protective effect of its major active ingredient, kinsenoside, in high glucose conditions was investigated in in vivo and in vitro experiments. In in vivo tests, kinsenoside (50 and 100 mg/kg) efficiently lowered blood glucose and cholesterol levels and it enhanced the oxidation resistance of diabetic mice induced by streptozotocin. In the in vitro assay, kinsenoside (20 and 50 μg/mL) markedly inhibited changes in various biochemical substances (nitric oxide (NO), lactic dehydrogenase (LDH), superoxide dismutase (SOD), and catalase (CAT)) in human umbilical vein endothelial cells (HUVECs) damaged by high glucose (35 mM) and restored vascular endothelial structure by balancing the matrix metalloproteinases–the tissue inhibitors of matrix metalloproteinases (MMP–TIMP) system. The vascular protective effects of kinsenoside were speculated to be attributed to oxidative stress inhibition and the reduction of nuclear factor kappa B (NF-κB) mRNA expression levels in high glucose conditions. Moreover, histological examination, including hematoxylin–eosin (H&E) staining, masson trichrome (Masson) staining, and periodic Schiff-methenamine (PASM) staining, greatly supported the morphological and functional amelioration of diabetes-related changes in mice aortas after kinsenoside (20 and 50 μg/mL) treatment. These results indicated that kinsenoside might be a promising agent for the treatment of diabetic vascular disease.  相似文献   

16.
Chao DC  Lin LJ  Kao ST  Huang HC  Chang CS  Liang JA  Wu SL  Hsiang CY  Ho TY 《Fitoterapia》2011,82(4):696-703
Zuo-Jin-Wan (ZJW) has been used to treat hepatocellular carcinoma in Asia. This study was to determine whether ZJW and its components blocked activator protein 1 (AP-1) and nuclear factor-κB (NF-κB) activities as well as tumor promotion in hepatoblastoma HepG2 cells. ZJW and its components, Coptis chinensis and Evodia rutaecarpa, inhibited AP-1 and NF-κB activities, and suppressed anchorage-independent growth of HepG2 cells. The major alkaloidal ingredients, berberine and evodiamine, inhibited AP-1 activities and/or NF-κB activation, and further suppressed hepatocellular transformation. In conclusion, ZJW and its constituents, berberine and evodiamine, suppressed tumor promotion primarily through AP-1 and/or NF-κB pathways in HepG2 cells.  相似文献   

17.
In this study, we analyzed Japanese National Forest Inventory data to investigate the geographical variation in the relationship between tree height and age for dominant trees, and the effects of climatic conditions on these relationships. Our analysis focused on Cryptomeria japonica forests in 13 regions of Japan. The age–height relationships were classified into two regional groups that were distinguished by their climatic conditions. Several categories of climatic variables (warmth, solar radiation, precipitation, and snow depth) were significantly correlated with the parameters of a model for the age–height relationships. Our results also suggest the existence of a latitudinal cline for the maximum tree height of C. japonica in Japan. In regions with cold temperatures, deep snow, low solar radiation, and low summer precipitation, C. japonica shows a late-maturity pattern for height increase, with slow initial growth and a large maximum size. In regions with the opposite climatic conditions, it shows an early-maturity pattern with fast initial growth and small maximum size.  相似文献   

18.
A better understanding of the hygro-mechanical behaviour of poplar wood (Populus alba L.) is proposed by means of restrained swelling tests. Small clear specimens were tested along their tangential direction in controlled climatic conditions; a dry climate (30 % relative humidity and 30 °C temperature) and a humid one (80 % relative humidity and 30 °C temperature) were cyclically set and kept constant each during 7 days. In these conditions, three matched specimens were tested at the same time along the tangential direction: specimen A free to shrink and swell, specimen B free to shrink and prevented from swelling beyond its initial dimension, specimen C prevented from shrinking and swelling. A specific device was set up to monitor strain and/or stress on each specimen. During the adsorption phase, compression forces (on specimens B and C) were measured, and during the desorption step, compression set shrinkage (compression strain at zero load) and tension stress (on specimens B and C, respectively) were measured. In this paper, the dedicated experimental device is presented and a deep analysis of experimental curves is then proposed by means of a rheological approach. By the analysis, some basic data are obtained (swelling coefficient, swelling pressure and compression set shrinkage), and a complex behaviour of wood made of reversible and irreversible phenomena is characterized.  相似文献   

19.
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20.
Diabetes mellitus is a metabolic disorder characterized by hyperglycemia due to either insufficiency of insulin or inability of cells to respond to insulin. Many clinical and experimental evidence have suggested the strong association between hyperglycemia, oxidative stress and diabetic complications. Therefore, the antidiabetic drugs with antioxidant potential would have a higher therapeutic value. To check its antidiabetic and antioxidant properties in vivo, experiments were done wherein mice were fed with Syndrex® in different schedules and/or made diabetic by intraperitoneal injection of streptozotocin. Animals fed with Syndrex® prior to the induction of diabetes by streptozotocin injection showed resistance to an increase in blood glucose levels. This treatment increased the activities of antioxidant enzymes namely, catalase, glutathione reductase and superoxide dismutase and reduced serum triglyceride and cholesterol levels as compared to those found in uncontrolled diabetic mice. Among the three different schedules used for Syndrex® treatment, the best effect was seen in the case of mice pretreated with Syndrex® prior to STZ injection. In our opinion, Syndrex® given along with insulin may reduce the amount of insulin dose required and because of its strong antioxidant activity would certainly help to reduce the development of diabetic complications.  相似文献   

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