共查询到20条相似文献,搜索用时 15 毫秒
1.
Wei Dai Linglin Fu Huahua Du Huitao Liu Zirong Xu 《Biological trace element research》2010,136(1):71-78
In order to investigate the effects of montmorillonite (MMT) on reducing dietary lead (Pb) toxicity to tilapia (Oreochromis niloticus), 240 fish were randomly divided into four treatments denominated as follows: control treatment (fed with a basal diet),
MMT treatment (fed with a basal diet added with 0.5% MMT), Pb treatment (fed with a basal diet added with 100 mg Pb per kilogram
dry weight (dw)), and Pb + MMT treatment (fed with a basal diet added with 100 mg Pb per kilogram dw and 0.5% MMT). Changes
in Pb accumulation, oxidative stress, and DNA damage in tilapia were measured after 60 days. DNA damage was assessed using
comet assay. The results showed that MMT supplemented in diet significantly reduced Pb accumulation in kidney and blood of
tilapia exposed to dietary Pb (P < 0.05). Malondialdehyde level decreased insignificantly while levels of total antioxidant capacity and glutathione (GSH),
activities of glutathione peroxidase, and superoxide dismutase increased insignificantly in kidney of tilapia in Pb + MMT
treatment as compared to Pb treatment (P > 0.05). Significant decreases in tail length, tail DNA, tail moment, and Olive tail moment of peripheral blood cells in
Pb + MMT treatment were observed when compared with Pb treatment (P < 0.05). The results indicated that dietary MMT supplementation could alleviate dietary Pb toxicity to tilapia effectively. 相似文献
2.
Chengwu Gu Songjian Chen Xijin Xu Liangkai Zheng Yan Li Kusheng Wu Junxiao Liu Zongli Qi Dai Han Gangjian Chen Xia Huo 《Neurochemical research》2009,34(6):1150-1156
Divalent metal transporter 1 (DMT1) can transport a large range of ions, including toxic lead (Pb) and cadmium (Cd), across
membranes. In this study, a total of 24 rats were divided into four groups for intragastrical perfusion treatment: control,
Pb alone, Cd alone, and Pb + Cd. Pb and Cd contents in blood were detected, and the mRNA and protein levels of DMT1 were analyzed
in the cerebellum, cortex, and hippocampus. Both Pb and Cd levels were elevated in all groups perfused with Pb and/or Cd,
except for Pb level in the Cd-alone group (P < 0.05). The mRNA level of DMT1 did not differ among the four groups (P > 0.05). However, the DMT1 protein expression was significantly increased by 0.9-, 1.0-, and 1.1-fold in cerebellum, cortex,
and hippocampus of the Pb + Cd group than in controls, respectively. Pb and Cd exposure can synergistically induce DMT1 protein
synthesis and has implications for transportation of toxic ions in the developing rat’s brain.
Chengwu Gu and Songjian Chen contributed equally to this work, they are joint first authors. 相似文献
3.
Kiziler AR Aydemir B Onaran I Alici B Ozkara H Gulyasar T Akyolcu MC 《Biological trace element research》2007,120(1-3):82-91
We measured the levels of malondialdehyde (MDA), protein carbonyls, glutathione S-transferase (GST) and reducte glutathione (GSH) in seminal plasma and spermatozoa from 95 subjects including 50 infertile
patients to evaluate the association between oxidative stress and damage and the components of the anti-oxidant defenses in
seminal plasma and spermatozoa of infertile subjects and concentrations of cadmium (Cd) and lead (Pb) in the blood and seminal
plasma because of tobacco smoke exposure. The reactive oxygen species (ROS) in spermatozoa were also evaluated by luminol
(5-amino-2,3-dihydro-1,4-phthalazinedione)-enhanced chemiluminescence assay. The sperm count, motility, and morphology in
the smokers infertile group were found to be lower than those in the fertile male group and nonsmokers infertile group (p < 0.001). Concentrations of Cd, Pb, MDA, protein carbonyls, and ROS levels in the smokers infertile group were significantly
higher than those in the fertile male and nonsmokers infertile male groups (p < 0.001). However, GSH levels and GST activities were decreased in the smokers infertile male group than those in the fertile
male and nonsmokers infertile male groups (p < 0.001). The results indicate that smoking could affect semen quality and oxidative lipid and protein damage in human spermatozoa.
From Pearson correlation analysis, positive correlations were demonstrated between the seminal plasma Cd and seminal plasma
protein carbonyls and between seminal plasma Pb and spermatozoa ROS levels in smokers of the subfertile group, while there
was a significant positive correlation between blood Cd and ROS levels in smokers of the fertile group. There was also a significant
negative correlation of the Cd level of the blood and GSH levels of the sperm and seminal plasma. These findings suggest that
cigarette smoking enhances the levels of Cd and Pb in seminal plasma and blood and the extent of oxidative damage associated
with a decrease in components of the anti-oxidant defenses in the sperm of infertile males. 相似文献
4.
Barton HJ 《Biological trace element research》2011,143(2):637-658
The population of about 300 6-year-old preschool children was studied for lead (Pb) and cadmium (Cd) in deciduous teeth, scalp
hair, and capillary blood. Zinc (Zn) content in hair was also measured due to its possible interferences with the elements
studied. The Pb and Cd contents were measured by graphite furnace atomic absorption spectrometry with Zeeman background correction,
and Zn, by flame method. Metal levels found were comparable to those in European countries. Positive correlations between
Pb and Cd in the same and different tissues were widespread (r = 0.23–0.68). A positive correlation was found between Pb in teeth and blood (r = 0.65, p < 0.001). Pb blood threshold 100 μg L−1 referred to 2.6 μg g−1 Pb in teeth. Predictability of this Pb teeth limit was 14% vs. 5% for Pb blood. Strong negative correlation was found between
hair Pb and Zn (r = −0.68, p < 0.001). Enhanced Cd and Zn levels in hair were associated with the household drinking water hardness. The associations
with some other environmental and behavioral factors were also presented and discussed. The results proved the advantage of
analysis of primary teeth for Pb exposure screening of preschool children. 相似文献
5.
Bing Chen Ludwig V. Lamberts Geert J. Behets Tingting Zhao Mingxiang Zhou Gang Liu Xianghua Hou Guangju Guan Patrick C. D’Haese 《Biological trace element research》2009,131(1):1-12
Whole blood and serum samples of Chinese stable chronic renal failure (CRF) patients (n = 81), hemodialysis patients (n = 135), posttransplant patients (n = 60), and subjects with normal renal function (NRF; N = 42) were collected, as well as water and dialysate samples from five dialysis centers. The concentration of selenium (Se),
lead (Pb), and cadmium (Cd) was measured by atomic absorption spectrometry. The mean serum Se levels in patients with different
degrees of renal failure were significantly lower than those of subjects with NRF (p < 0.01). Pb levels were not increased in renal failure patients, while the Cd levels in patients with various degrees of
renal failure were higher than in subjects with NRF (p < 0.05). After correcting the results of Pb and Cd for hematocrit (Hct) however, Pb levels of dialysis patients were also
increased. In the dialysis population under study, blood Pb and Cd levels were closely related to the time on dialysis, while
contamination of the final dialysate may also contribute to the increased blood Cd and to a less extent Pb levels. Correction
for Hct may be recommended to accurately compare blood Pb and Cd levels in dialysis patients and CRF patients with varying
degrees of anemia to those of subjects with NRF. 相似文献
6.
Heavy Metals in Eight Edible Fish Species from Two Polluted Tributaries (Aik and Palkhu) of the River Chenab,Pakistan 总被引:1,自引:0,他引:1
Concentration of heavy metals (lead (Pb), cadmium (Cd), chromium (Cr), and copper (Cu)) was determined in the liver, gills,
kidneys, and muscles of eight edible fish species (Channa punctata, Cirrhinus reba, Labeo rohita, Heteropneustes fossilis, Mystus cavasius, Oreochromis niloticus, Puntius sophore, and Wallago attu) from upstream and downstream zones of the Nullah Aik and Palkhu tributaries of the River Chenab located in the Sialkot district
known for its tanning industries worldwide. The pattern of metal accumulation in studied organs was in the order: Cr > Pb > Cu > Cd.
Liver showed greater metal accumulation, followed by gills, kidneys, and muscles. Accumulation of Pb and Cr was significantly
different in organs between upstream and downstream zones. Accumulation was greater in fish species dwelling downstream, indicating
impairment of ambient stream water due to untreated discharge of industrial and municipal effluents into studied streams.
Highest concentration of Pb and Cr and lowest of Cd was detected in H. fossilis whereas Cu showed higher concentration and Cr lowest concentration in P. sophore. In contrast, lower concentration of Pb and Cu was recorded in M. cavasius, O. niloticus, and W. attu. Mean concentrations of Cd, Cr, and Cu were higher in pre-monsoon compared to post-monsoon season. Measured concentrations
of Pb, Cd, and Cr in muscles of species such as C. punctata, W. attu, L. rohita, P. sophore, and O. niloticus were above permissible limits of heavy metals for human consumption, indicating potential health risks. Therefore, these
fish species from studied locations should be avoided for human diet. 相似文献
7.
Afridi HI Brabazon D Kazi TG Naher S Nesterenko E 《Biological trace element research》2011,143(3):1367-1382
The abnormal metabolism of metal ions plays an important role in health and disease conditions, and studies about them have
been attracting significant interest. The aim of our study was to assess the heavy metals (cadmium (Cd), nickel (Ni), lead
(Pb), and zinc (Zn)) in scalp hair samples of 50 Irish and 78 Pakistani hypertensive patients of an urban population together
with 50 Irish and 96 Pakistani non-hypertensive male subjects in the age group of 30–50 years. The concentrations of trace
and toxic elements were measured by inductively coupled plasma–atomic emission spectrophotometer and atomic absorption spectrophotometer
before microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference
materials, and by the conventional wet acid digestion method on the same certified reference materials and on real samples.
The recovery of all the studied elements was found to be in the range of 97.5–99.7% in certified reference material. The results
of this study showed that the mean values of cadmium, nickel, and lead were significantly higher in scalp hair samples of
both Pakistani and Irish hypertensive patients than in referents (p < 0.001); whereas, the concentration of zinc was lower in the scalp hair samples of hypertensive patients of both genders.
The deficiency of zinc and the high exposure of trace and toxic metals may be the risk factors associated with hypertension. 相似文献
8.
Tomza-Marciniak A Pilarczyk B Bąkowska M Pilarczyk R Wójcik J 《Biological trace element research》2011,143(2):863-870
Concentrations of cadmium, lead, iron, zinc, copper, chromium, nickel, aluminium and arsenium were analysed in blood serum
of cattle from organic (n = 20) and conventional (n = 21) farms. The elements were determined by inductively coupled plasma atomic emission spectrometry using an Optima 2000
DV instrument (Perkin Elmer Inc.). Animals from the organic farm were characterised by significantly lower (P < 0.01) serum concentrations of Pb, Zn, Fe, Cu, Cr, Ni, As and Al compared to animals from the conventional farm. The concentration
of Cd was similar in animals from both organic and conventional farms. The concentration of toxic elements in cattle from
organic and conventional farms studied was very low. The trace essential elements were generally within the adequate ranges
except Zn and Cu, which were deficient. In organically reared animals, also serum Fe content was below the critical level
for diagnosing iron deficiency. Pb was significantly correlated with Cd, Zn, Fe, Cu and Ni. A significant positive correlation
between the concentration of Cd and Zn, Cu and Ni concentrations was only observed in cows from the organic farm. The present
results suggest that organically raised animals are less exposed to harmful environmental influences such as the environmental
pollution with heavy metals. On the other hand, these animals are at a greater risk of mineral deficiency compared to animals
kept on conventional farms. 相似文献
9.
This study describes the toxic effects of different prominent aquatic pollutants—heavy metals (Cd & Pb), pesticides (alphamethrin
and deltamethrin) and salt (NaCl)—on the intracellular proline content in the cyanobacterium, Westiellopsis prolifica–Janet strain–NCCU331. Despite a reduction in growth (measured as chlorophyll a content), the intracellular proline content increased in the presence of heavy metals, pesticides and high salt concentration.
The intracellular cyanobacterial proline accumulation was more pronounced under salt stress than in the presence of pesticides
and heavy metals. We have also compared whether or not anionic components influence heavy metal toxicity. It was found that
the chlorides of Cd and Pb were more toxic than the NO3 and the order of toxicity was CdCl2 > PbCl2 > Cd (NO3)2 > Pb (NO3)2. Among pyrethroids, deltamethrin was more toxic than alphamethrin.
Presented at the 6th Meeting of the Asian Pacific Society of Applied Phycology, Manila, Philippines. 相似文献
10.
Prakash Pillai Ritesh Patel Chirayu Pandya Sarita Gupta 《Journal of biochemical and molecular toxicology》2009,23(6):419-431
Liver has evolved complex enzymatic mechanisms to detoxify a wide array of xenobiotic substances, ranging from dietary components to environmental toxins to pharmaceuticals. Activities of many steroid‐metabolizing enzymes in adult rat liver microsomes are sexually differentiated. Toxic effects of lead and cadmium on hepatic tissue have been well established in our earlier studies. We thus monitored the effects of gestational and lactational coexposure to lead and cadmium on hepatic phase I and phase II xenobiotic‐ and steroid‐metabolizing enzyme activities in both male and female F1 generation postnatal day (PND) 56 rats. Adult pregnant female rats were treated subcutaneously [0.05 mg/(kg body wt. day)] with sodium acetate (control group), lead acetate, and cadmium acetate separately and in combination throughout the gestational and lactational period. Hepatic phase I xenobiotic‐metabolizing enzymes (NADPH‐ and NADH‐cytochrome c reductase) activities significantly decreased significantly in all the metal‐treated groups in both PND 56 male and female rats as compared with the control group. Hepatic phase II enzymes (uridine diphosphate‐glucuronosyl transferase, γ‐glutamyl transpeptidase, glutathione‐S‐transferase, 17‐β‐hydroxysteroid oxidoreductase) were also highly susceptible to all the metal‐treated groups. The observed alterations in the oxidative stress and biochemical parameters in the liver of F1 generation male and female rats resulted from an independent effect of lead and/or cadmium and also from their interaction. Results suggest that early developmental exposure to lead and cadmium both alone and in combination can suppress the hepatic xenobiotic‐metabolizing enzyme activities in the liver of F1 generation male and female rats in a sex‐dependent manner. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:419–431, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20305 相似文献
11.
This study assessed the impact of either cadmium chloride (Cd) or sodium selenite (Se) alone or in combination on male Sprague–Dawley
rats. For this purpose, body and liver weights, comet and TUNEL assays, histological analysis and levels of lipid peroxidation
and antioxidants in liver were determined in four groups of male Sprague–Dawley rats. The rats were given subcutaneous doses
of 1 mg/kg body weight (BW) of either normal saline (control = Ct) or Cd or Se or Cd plus Se (Cd + Se) on alternate days for
4 weeks. The Cd group showed increased DNA damage, apoptosis and hepatic levels of lipid peroxidation and altered histology.
Conversely, the antioxidant levels in this group were decreased as compared with the control group. The Se group also showed
DNA damage, apoptosis and altered histology and reduced catalase activity, but it was less severe than the Cd group. In the
Cd + Se group, ameliorating effects of Se on Cd-induced changes were observed. While the Se was able to curtail the toxic
effect of Cd, the Cd or Se alone were genotoxic and cytotoxic for rats receiving a high pharmacological but non-fatal dose
of 1 mg/kg BW. 相似文献
12.
Pan Zhenzhen Guo Yun Xiang Hongxia Hui Yu Ju Huili Xu Shiyao Li Ling 《Biological trace element research》2020,194(1):115-120
Biological Trace Element Research - Accumulating evidence has shown that toxic metals exposure can have adverse effects on children, but the effects of blood Pb, Hg, and Cd co-exposure on pulmonary... 相似文献
13.
The aim of the present study was to evaluate the role of arbuscular mycorrhizal (AM) fungi on metal uptake, oxidative effects
and antioxidant defence mechanisms under cadmium (Cd) and lead (Pb) stresses in Cajanus cajan (L.) Millsp. (pigeonpea). Treatments consisted of two concentrations each of Cd (25 and 50 mg/kg of soil) and Pb (500 and
800 mg/kg of soil) singly as well as in combination. Both metals induced oxidative damage through increased lipid peroxidation,
electrolyte leakage and hydrogen peroxide levels, but Cd was found to be more toxic than Pb. Compared with the effects of
Cd or Pb alone, the combination of Cd and Pb acted synergistically; however, Pb immobilisation in soil controlled the uptake
of Cd in plants. There was a direct correlation between the type of genotype, heavy metal content and oxidative damage in
concentration dependent manner. Superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) increased under stress. The
toxicity symptoms of the metal stress were significantly higher in Sel-141-97 genotype when compared with Sel-85 N. The high
ratio of glutathione to its oxidised form, glutathione disulfide (GSH/GSSG), could be restored by means of higher glutathione
reductase (GR) activity and increased GSH synthesis in mycorrhizal stressed plants. AM inoculations with Glomus mosseae significantly arrested uptake of Cd and Pb into the root system and further translocation into the above ground parts and
led to decreased lipid peroxidation and electrolyte leakage. Increased activities of SOD, CAT, POX as well as GR were observed
in all mycorrhizal stressed plants. 相似文献
14.
Kazi TG Jalbani N Kazi N Arain MB Jamali MK Afridi HI Kandhro GA Sarfraz RA Shah AQ Ansari R 《Biological trace element research》2009,127(1):16-27
The determination of toxic metals (TMs) in the biological samples of human beings is an important clinical screening procedure.
The aim of this work is to determine total content of TMs, aluminum (Al), cadmium (Cd), nickel (Ni), and lead (Pb) in scalp
hair samples of chronic kidney male patients (CKPs) on maintenance hemodialysis, during the period of 2005–2007. The study
included 115 CKPs (all smokers) and 150 controls or referents [82 (nonsmokers) and 68 (smokers)]. Both controls and patients
(males) were of the same age group (ranged 25–55 years), socioeconomic status, localities, and dietary habits. The scalp hair
samples were analyzed by electrothermal atomic absorption spectrometer, prior to microwave-induced acid digestion. The accuracy
of the total Al, Cd, Ni, and Pb measurements was tested by simultaneously analyzing certified reference material (human hair
NCS ZC81002). No significant differences were observed between the analytical results and the certified values (paired t test at p > 0.05). The levels of TMs in scalp hair samples of patients were found to be higher as compared to control nonsmoker and
smokers. Moreover, the study shows that levels of Al, Cd, Ni, and Pb in scalp hair samples may be useful to evaluate the impact
of cigarette smoking in kidney failure patients. 相似文献
15.
In the present study, the association of arsenic, cadmium, lead, and nickel between scalp hair samples and mortality from
myocardial infarction (MI) patients at first, second, and third heart attack was studied. The biological samples of 130 MI
patients (77 male and 53 female) age ranged (45–60 years), were collected and 61 healthy persons of same age group (33 male
and 28 female) was selected as control subjects. The toxic elements (TEs) in biological samples were assessed by the electrothermal
atomic absorption spectrophotometry prior to microwave-assisted acid digestion. The validity of methodology was checked by
the certified human hair reference material (BCR 397). It was observed during the study that 78% of 32 patients of the third
MI, age >50 years were expired. In these subjects, the level of As, Cd, Ni, and Pb were increased by 10.6%, 19.5%, 15.7%,
and 9.8% in the scalp hair as compared to those who tolerated third MI attack (p = 0.12). The high level of toxic metals may play a role in the development of heart disease in the subjects of this study. 相似文献
16.
Alieu Mohamed Bah Huaxin Dai Jing Zhao Hongyan Sun Fangbin Cao Guoping Zhang Feibo Wu 《Biological trace element research》2011,142(1):77-92
This study investigates the modulation of antioxidant defence system of Typha angustifolia after 30 days exposure of 1 mM chromium (Cr), cadmium (Cd), or lead (Pb). T. angustifolia showed high tolerance to heavy metal toxicity with no visual toxic symptom when exposed to metal stress, and Cd/Pb addition
also increased plant height and biomass especially in Pb treatment. Along with increased Cr, Cd, and Pb uptake in metal treatments,
there was enhanced uptake of plant nutrients including Ca and Fe, and Zn in Pb treatment. A significant increase in malondialdehyde
(MDA) content and superoxide dismutase (SOD) and peroxidase (POD) activities were recorded in plants subjected to Cr, Cd,
or Pb stress. Furthermore, Pb stress also improved catalase (CAT), ascorbate peroxidase (APX), and glutathione peroxidase
(GPX) activities; whereas Cr stress depressed APX and GPX. The results indicate that enzymatic antioxidants and Ca/Fe uptake
were important for heavy metal detoxification in T. angustifolia, stimulated antioxidative enzymes, and Ca, Fe, and Zn uptake could partially explain its hyper-Pb tolerance. 相似文献
17.
Males (n=34) and females (n=23) of long-tailed duck (Clangula hyemalis) collected on the southern coast of the Baltic Sea in winter were studied to determine brain tissue concentration of iron
(Fe), zinc (Zn), copper (Cu), manganese (Mn), and cadmium (Cd). There were no significant differences in the concentration
of metals between males and females, except for Cd, the concentration of which in male brains was twice that of the females.
In the brains of 20 birds (41% male and 26% female), the lead (Pb) concentration exceeded 1 μg/g wet wt. In all the duck brains
examined, Spearman correlation coefficients were significant and positive for Zn−Mn, Cu−Mn, Cu−Fe, and Pb−Fe; a negative correlation
was found for Pb−Zn. Additionally, female brains showed a positive correlation between Pb and Fe. The results obtained were
compared with literature data for diving and nondiving anseriforms and birds of other taxa. It seems that concentration of
heavy metals in the brain tissue of birds reflect natural adaptations (e.g., for diving) as well as effects of environmental
pollution. 相似文献
18.
Hassan Imran Afridi Tasneem Gul Kazi Naveed Kazi Ghulam Abbas Kandhro Jameel Ahmed Baig Mohammad Khan Jamali Mohammad Balal Arain Abdul Qadir Shah 《Biological trace element research》2011,139(3):368-268
The pathogenesis of some cardiovascular diseases (CVDs) has been altered with changes in the balance of certain trace and
toxic elements. The aim of the present study was to assess the role of zinc (Zn) and cadmium (Cd) in smoker and nonsmoker
male CVD patients (n = 457) of two age groups (31–45) and (46–60). The both elements were determined in biological samples (scalp hair, blood,
and urine) of CVD patients and healthy referents for comparison purpose. The concentrations of Zn and Cd were measured by
atomic absorption spectrophotometer prior to microwave-assisted acid digestion. It was observed that the mean values of Cd
were significantly higher in the biological samples of smokers CVD as compared to nonsmoker CVD patients, while the level
of Zn was lower in both smoker and nonsmoker patients. The concentrations of Zn in whole blood and scalp hair samples were
lower in CVD patients as compared to referents (p > 0.001). Results showed significant changes of levels of Cd and Zn in blood and scalp hair samples of CVD patients when
compared with healthy referents, while reverse in the case of urine samples. It was observed that low Zn levels were associated
with both smoker and nonsmoker CVD patients, while increased cadmium accumulation was observed in smoker patients as compared
to nonsmoker patients (p > 0.025). 相似文献
19.
Dana Kotyzová Pavla Černá Ladislav Lešetický Vladislav Eybl 《Biological trace element research》2010,136(3):287-293
Although the metabolic and toxicological interactions between essential element selenium (Se) and toxic element cadmium (Cd)
have been reported for a long time, the experimental studies explored mostly acute, high-dose interactions. Limited data are
available regarding the effects of Se-deficiency on toxicokinetics of cadmium, as well as on the levels of key trace elements—copper,
zinc, and iron. In the present study, male and female Wistar weanling rats (n = 40/41) were fed either Se-deficient or Se-adequate diet (<0.06 or 0.14 mg Se per kilogram diet, respectively) for 12 weeks,
and from week 9 were drinking water containing 0 or 50 mg Cd/l as cadmium chloride. At the end of the 12-week period, trace
element concentrations were estimated by AAS. Selenium-deficient rats of both genders showed significantly lower accumulation
of cadmium in the liver, compared to Se-adequate rats. Zinc and iron hepatic levels were not affected by Se-deficiency. However,
a significant elevation of copper was found in the liver of Se-deficient rats of both genders. Cadmium supplementation increased
zinc and decreased iron hepatic level, regardless of Se status and decreased copper concentration in Se-adequate rats. Se-deficiency
was also found to influence the effectiveness of cadmium mobilization in male rats. 相似文献
20.
Stress Responses of Zea mays to Cadmium and Mercury 总被引:2,自引:1,他引:1
Rubén Rellán-Álvarez Cristina Ortega-Villasante Ana Álvarez-Fernández Francisca F. del Campo Luis E. Hernández 《Plant and Soil》2006,279(1-2):41-50
A hydroponic experiment was carried out to characterize the oxidative stress responses of maize seedlings (Zea mays L. cv. Dekalb DK604) to cadmium (Cd) and mercury (Hg). Plants were grown hydroponically for 7 days in a nutrient solution
supplemented with several concentrations of Cd and Hg: 0.0 (control), 6 or 30 μM. Growth was inhibited by both metals. The
effect was more severe in plants exposed to Hg. Oxidative stress was caused by the exposure to the metals, as quantified by
malondialdehyde and carbonyl accumulation, by-products of lipid peroxidation and protein oxidation, respectively. The activity
of ascorbate peroxidase (APX) and superoxide dismutase (SOD), enzymes involved in the scavenging of reactive oxygen species,
were measured upon metal treatment. We found an activation of a cytosolic APX isoform, as identified by using a specific polyclonal
antiserum. However, there were negligible changes in SOD activity. Analysis of thiol-peptides revealed that at 6 μM Cd a remarkable
increase in root reduced glutathione (GSH) content occurred, and little effect on the relative content of oxidised glutathione
(GSSG) was observed. However, at 30 μM Cd and in plants exposed to 6 and 30 μM of Hg, GSH root content either remained stable
or decreased significantly, while the proportion of GSSG increased. Moreover, only Cd was able to induce accumulation of phytochelatins
at both assayed concentrations. Apparently, Hg was more toxic than Cd, as inferred from the magnitude of the changes found
in the physiological parameters tested. 相似文献