Protective effects of proline against cadmium toxicity in micropropagated hyperaccumulator, Solanum nigrum L.

Solanum nigrum is a newly discovered Cd-hyperaccumulator. In the present study, the protective effects of proline against cadmium toxicity of callus and regenerated shoots of S. nigrum are investigated based on a high frequency in vitro shoot regeneration system. Proline pretreatment reduces the reactive oxygen species levels and protects the plasma membrane integrity of callus under cadmium stress, and therefore improves the cadmium tolerance in S. nigrum. Inductively coupled plasma mass spectroscopy analysis shows that exogenous proline increases the cadmium accumulation in callus and regenerated shoots of S. nigrum. Further analysis indicates that the improvement of cadmium tolerance caused by proline pretreatment is correlated with an increase of superoxide dismutase and catalase activity and intracellular total glutathione content. The interaction between proline and enzymic or non-enzymic antioxidants is discussed.     

Histological and histochemical alterations in the liver induced by lead chronic toxicity

Adult males of the Wistar albino rats (Rattus norvegicus) were exposed to lead acetate trihydrate in drinking water (0.0%, 0.25%, 0.5%, 1% and 2% for 1–12 months) to investigate histological and histochemical alterations induced by lead intoxication in the liver. Chronic exposure to subtoxic concentrations of lead produced changes in the hepatocytes, portal triads and the sinusoids. The alterations in the hepatocytes were mainly anisokaryosis, nuclear vesiculation, binucleation, cytoplasmic inclusions, cytoplasmic swelling, hydropic degeneration, necrosis and reduction in glycogen content. In addition, portal triads mild chronic inflammation, Kupffer cells hyperplasia and occasional fatty change were seen together with hemosiderosis. No portal fibrosis or cirrhosis was detected due to chronic subtoxic doses of lead exposure in the liver of any member of the dose groups over the entire period of the study. Chronic lead exposure also increased the activities of alkaline phosphatase and α-glycerophosphate-dehydrogenase which might be an adaptation to the metabolic, structural and functional changes in the organelles of hepatic cells due to lead intoxication. The findings revealed that chronic exposure to lead produced significant histological and histochemical changes in the liver of the Wistar albino rats.     

Cadmium toxicity affects chlorophyll a and b content,antioxidant enzyme activities and mineral nutrient accumulation in strawberry

Background

Cadmium (Cd) is well known as one of the most toxic metals affecting the environment and can severely restrict plant growth and development. In this study, Cd toxicities were studied in strawberry cv. Camarosa using pot experiment. Chlorophyll and malondialdehyde (MDA) contents, catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) activities and mineral nutrient concentrations were investigated in both roots and leaves of strawberry plant after exposure Cd.

Results

Cd content in both roots and leaves was increased with the application of increasing concentrations of Cd. We found higher Cd concentration in roots rather than in leaves. Chlorophyll a and b was decreased in leaves but MDA significantly increased under increased Cd concentration treatments in both roots and leaves. SOD and CAT activities was also increased with the increase Cd concentrations. K, Mn and Mg concentrations were found higher in leaves than roots under Cd stress. In general, increased Cd treatments increased K, Mg, Fe, Ca, Cu and Zn concentration in both roots and leaves. Excessive Cd treatments reduced chlorophyll contents, increased antioxidant enzyme activities and changes in plant nutrition concentrations in both roots and leaves.

Conclusion

The results presented in this work suggested that Cd treatments have negative effect on chlorophyll content and nearly decreased 30% of plant growth in strawberry. Strawberry roots accumulated higher Cd than leaves. We found that MDA and antioxidant enzyme (CAT, SOD and APX) contents may have considered a good indicator in determining Cd tolerance in strawberry plant.     

Hesperidin ameliorates heavy metal induced toxicity mediated by oxidative stress in brain of Wistar rats

Cadmium (Cd) induces neurotoxicity owing to its highly deleterious capacity to cross the blood brain barrier (BBB). Recent studies have provided insights on antioxidant properties of bioflavonoids which have emerged as potential therapeutic and nutraceutical agents. The aim of our study was to examine the hypothesis that hesperidin (HP) ameliorates oxidative stress and may have mitigatory effects in the extent of heavy metal-induced neurotoxicity. Cd (3 mg/kg body weight) was administered subcutaneously for 21 days while HP (40 mg/kg body weight) was administered orally once every day. The results of the current investigation demonstrate significant elevated levels of oxidative stress markers such as lipid peroxidation (LPO) and protein carbonyl (PC) along with significant depletion in the activity of non-enzymatic antioxidants like glutathione (GSH) and non-protein thiol (NP-SH) and enzymatic antioxidants in the Cd treated rats’ brain. Activity of neurotoxicity biomarkers such as acetylcholinesterase (AchE), monoamine oxidase (MAO) and total ATPase were also altered significantly and HP treatment significantly attenuated the altered levels of oxidative stress and neurotoxicity biomarkers while salvaging the antioxidant sentinels of cells to near normal levels thus exhibiting potent antioxidant and neuroprotective effects on the brain tissue against oxidative damage in Cd treated rodent model.     

Secoisolariciresinol diglucoside protects against cadmium-induced oxidative stress-mediated renal toxicity in rats

BackgroundCadmium is a well known environmental pollutant and strong toxic heavy metal, that causes oxidative damage to various organs of the body, including the kidney. Cadmium (II) chloride (CdCl₂) is a water-soluble crystalline form, which exhibits a higher affinity with chlorides at the target site. The current study examined the protective effects of Secoisolariciresinol diglucoside (SDG), a principal lignan extracted from flaxseeds against CdCl₂-induced renal toxicity in rats.MethodsTwenty four healthy male Wistar rats with four groups of six animals each were used in the study. Group-1- Control was administered with saline. Group-2 –was treated with SDG; Group-3 with CdCl₂ alone, and Group-4 were treated with CdCl₂ plus SDG. The effect of Cd on kidney was assessed in terms of various parameters like lipid peroxidation, production of Nitric oxide (NO) and Myeloperoxidase (MPO), and kidney function markers like uric acid, urea, and creatinine. The levels of antioxidant molecules like glutathione content and the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase were also measured, apart from histopathological studies.ResultsThe animals that received CdCl₂, exhibited changes in the concentration of Cd in the kidney. The levels of kidney function markers like uric acid, urea, and creatinine were found to be abnormal in serum, and also there was a drastic decrease in the levels of glutathione content and the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. The treatment of SDG significantly decreased (p < 0.05) the levels of NO and MPO in the animals treated with CdCl₂ plus SDG when compared to the animal group treated with CdCl₂ alone. The treatment of SDG before CdCl2 injection exhibited significant changes in the activity of the antioxidant enzymes, which was evidenced by the restoration in their activities, when compared to CdCl2 alone treated group (p < 0.05), as observed in the results of histopathology.ConclusionsThe findings of the present investigation suggested that SDG exhibited anti-oxidant, anti-apoptotic and renoprotective properties. Thus, SDG may act as a supramolecular binding component and naturally occurring metal chelating agent for metal cations like Cd²⁺. Therefore, flaxseed lignan-SDG can be used as a therapeutic agent against nephrotoxicity caused by cadmium. However, detailed future studies are needed to know the underlying mechanism of action of SDG against the Cd and other heavy metals induced nephrotoxicity.     

Antioxidant effect of vitamin E treatment on some heavy metals-induced renal and testicular injuries in male mice

Toxic heavy metals in water, air and soil are global problems that are a growing threat to humanity. Heavy metals are widely distributed in the environment and some of them occur in food, water, air and tissues even in the absence of occupational exposure. The antioxidant and protective influences of vitamin E on a mixture of some heavy metals (Pb, Hg, Cd and Cu)-induced oxidative stress and renal and testicular injuries were evaluated in male mice. Exposure of mice to these heavy metals in drinking water for seven weeks resulted in statistical increases of plasma creatinine, urea and uric acid concentrations. The levels of glutathione (GSH) and superoxide dismutases (SOD) in kidney and testis tissues were significantly declined. Moreover, the histopathological evaluation of kidney and testis showed severe changes in mice treated with these heavy metals. Administration of vitamin E protected the kidney and testis of mice exposed to heavy metals as evidenced by appearance of normal histological structures, insignificant changes in the values of plasma creatinine, urea and uric acid, and the levels of kidney GSH and SOD, while the levels of testis GSH and SOD were notably decreased. These data suggest that the administration of vitamin E protects against heavy metals-induced renal and testicular oxidative stress and injuries.     

Hormonal effects of lead acetate in the male rat: mechanism of action

Environmental exposure to toxic levels of lead occurs in a number of industries with potential adverse effects on the reproductive capacity of exposed men. Using a rat model, we previously reported that dietary exposure to lead resulted in suppressed spermatogenesis and testosterone levels without significant changes in luteinizing hormone (LH). In this study, to identify more specifically the site of lead's toxic actions on the hypothalamic-pituitary-testicular axis, the response of lead-treated male rats as compared to control animals to naloxone, gonadotropin-releasing hormone (GnRH), and LH stimulation was studied. Three groups of 52-day-old Wistar rats were allowed access to either deionized distilled water containing no lead acetate or a 0.3% lead acetate solution for 30 days. In each study group, 10 control and 10 lead-treated animals were anesthetized prior to cardiac puncture and collection of serum for the measurement of lead level and baseline LH (Groups I and II) or testosterone levels (Group III). In Group I, 20 min after an i.p. injection of naloxone (1.5 mg/kg/BW), the animals were killed by decapitation, and serum was collected for LH measurement. Thirty minutes after an i.p. injection of GnRH (100 ng/100 gm BW), Group II animals were killed by decapitation, and serum was collected for LH. Sixty minutes after an injection of LH (100 mg/100 mg BW), serum was collected from Group III animals for testosterone measurement. All control animals and lead-treated animals consumed similar volumes of water. Control animals had undetectable levels of lead in their blood. Lead-treated animals had mean blood lead values of 30 micrograms/dl +/- 5 micrograms/dl.(ABSTRACT TRUNCATED AT 250 WORDS)     

Alleviative effects of quercetin and onion on male reproductive toxicity induced by diesel exhaust particles

Diesel exhaust particles (DEPs) are particulate matter from diesel exhaust that contain many toxic compounds, such as polyaromatic hydrocarbons (PAHs). Some toxicities of PAH are thought to be expressed via aryl hydrocarbon receptors (AhRs). The male reproductive toxicity of DEPs might depend on AhR activation induced by PAHs. We hypothesized that AhR antagonists protect against the male reproductive toxicity of DEPs. Quercetin is a flavonoid and a well-known AhR antagonist, while onion contains many flavonoids, including quercetin. Hence, we examined whether quercetin and onion have alleviative effects against the male reproductive toxicity induced by DEPs. BALB/c male mice were fed quercetin- or onion-containing diets and received 10 injections of DEP suspension or vehicle into the dorsal subcutaneous layer over 5 weeks. The mice were euthanized at 2 weeks, after the last treatment, and their organs were collected. Daily sperm production and total incidence of sperm abnormalities were significantly affected in the DEP groups as compared with the vehicle group, but the total incidence of sperm abnormalities in the quercetin + DEP-treated mice was significantly reduced as compared with the DEP-treated mice. The numbers of Sertoli cells were significantly decreased in DEP-treated mice as compared with the vehicle-treated mice, but, the numbers of Sertoli cells were significantly increased in the quercetin and the onion + DEP-treated mice as compared with the DEP-treated mice. These results clearly indicate alleviative effects of quercetin and onion against the male reproductive toxicity induced by DEP.     

Antioxidant effects of Emblica officinalis and Zingiber officinalis on arsenic and lead induced toxicity on Albino rats

It is of interest to document the effect of Emblica officinalis (E. officinalis) and Zingiber officinalae (Z. officinalae) leaf extract on reactive oxygen species, antioxidant potential changes in arsenic and lead-induced toxicity in male rats. We used 8 groups of adult male Wistar rats with 1 control group for this study. The animals were divided into Group I: Control and Group II: Lead and sodium arsenite induced rats (animals were induced for metal toxicity by the combined administration of arsenic (13.8 mg/ kg body weight) and lead (116.4 mg/kg body weight). These doses were administered by gastric intubation during 14 consecutive days using known standard procedures. Arsenic and lead induced rats treated with ethanolic extract of Emblica officinalis (60 mg/kg body weight/day, orally for 45 days) are group III rats. Group IV animals are arsenic and lead induced rats treated orally with ethanolic extracts of E. officinalis (120 mg/kg body weight/day for 45 days). Group V animals are arsenic and lead induced rats treated orally with ethanolic extracts of Z. officinalae (60 mg/kg body weight/day for 45 days). Group VI animals are arsenic and lead induced rats orally treated with ethanolic extracts of Zingiber officinalis (120 mg/kg body weight/day for 45 days). Group VII animals are arsenic and lead induced rats treated orally with ethanolic extracts of E. officinalis and Z. officinalae (60 + 60 mg/kg body weight/day for 45 days). Group VIII animals are arsenic and lead induced rats treated orally with ethanolic extracts of E. officinalis and Z. officinalae (120 + 120 mg/kg body weight/day, orally for 45 days). Normal Control animals were treated orally with ethanolic extracts of E. officinalis (120mg/kg body weight) + Z. officinalae (120mg/kg body weight) for 45 days. The control and experimental animals were then subjected to analysis for oxidative stress markers such as H2O2, *OH, and lipid peroxidation (LPO), antioxidant enzymes in addition to liver and kidney function markers. Results: Arsenic and lead induced rats showed a significant increase in the levels of reactive oxygen species (H2O2, OH* and LPO) with concomitant alterations in the renal and liver tissues. However, enzymic and non-enzymic antioxidant levels were decreased. Nevertheless, an oral effective dose of E. officinalis and Z. officinalae (120 + 120 mg/kg body weight/day increased the antioxidant enzymes and retrieved the altered levels of ROS and LPO that were induced by arsenic and lead. Thus, we show that E. officinalis and Z. officinalae leaf extract exhibits nephroprotective and hepatoprotective role through the restoration of reactive oxygen species and antioxidant enzymes in the kidney and liver tissue of Arsenic and Lead-induced nephrotoxicity and hepatotoxicity in rats. Hence, E. officinalis and Z. officinalae leaf extract are potential therapeutic options for the treatment of metal toxicity-induced kidney and liver diseases.     

Impact of Moringa oleifera leaf extract in reducing the effect of lead acetate toxicity in mice

This study aimed to assess the impact of Moringa oleifera (M. oleifera) leaf extract against the poisoning of lead acetate; therefore, sixty mice were allocated into 4 groups with 15 in each, as G1) blank control, G2) supplied with 300 mg/kg body weight (BWT). M. oleifera extract, G3) supplied with 60 mg/kg BWT of lead acetate [Pb(C₂H₃O₂)₂], and G4) supplied with extract of M. oleifera + lead acetate. The liver enzymes were elevated post-treatment with Pb(C₂H₃O₂)₂, which then lowered to almost the normal level when M. oleifera was supplied to mice previously treated with Pb(C₂H₃O₂)₂. The values in (G3) decreased when compared with G1 (92.33 ± 12.99, 21.67 ± 2.91 and 98.00 ± 13.20 U/L, respectively. Also, the cholesterol and low-density lipoprotein levels were elevated post-supplementation with M. oleifera and Pb(C₂H₃O₂)₂. Pb(C₂H₃O₂)₂ improves the lipid profile, whereas M. oleifera pretreatment reduced cholesterol (CHOL), high density low cholesterol (HDL-c), and low-density low cholesterol (LDL-c) levels in animals fed Pb(C₂H₃O₂)₂. Pb(C₂H₃O₂)₂ elevates the total protein but lowers the total bilirubin and triglycerides post M. oleifera treatment and Pb(C₂H₃O₂)₂ when contrasted with G1. The protective effect of M. oleifera was caused by the fact that it lowered triglycerides (TG) and total bilirubin (TBIL) and raised total protein (TP). After administration of Pb(C₂H₃O₂)₂, the histological examination revealed alterations in the hepatocytes and kidneys of G3. Also, the liver and kidney cells in mice supplied with M. oleifera after Pb(C₂H₃O₂)₂ poisoning recovered. In conclusion, Pb is toxic, and the usage of M. oleifera partially enhances the negative impacts induced by Pb(C₂H₃O₂)₂.     

Blood lead levels and cumulative blood lead index (CBLI) as predictors of late neurodevelopment in lead poisoned children

Objective: To find the best lead exposure assessment marker for children.

Methods: We recruited 11 children, calculated a cumulative blood lead index (CBLI) for the children, measured their concurrent BLL, assessed their development, and measured their bone lead level.

Results: Nine of 11 children had clinically significant neurodevelopment problems. CBLI and current blood lead level, but not the peak lead level, were significantly or marginally negatively associated with the full-scale IQ score.

Conclusion: Lead exposure at younger age significantly impacts a child’s later neurodevelopment. CBLI may be a better predictor of neurodevelopment than are current or peak blood lead levels.     

Bioaccumulation and histopathological alteration of total lead in selected fishes from Manila Bay,Philippines

This study aims to assess the bioaccumulation of total lead and the effect of heavy metal on the muscles of fish obtained in the coastal lagoon of the Manila Bay. Fish species muscles were assessed for lead concentrations and were examined for histological alterations. Results showed that lead bioaccumulation in the muscles, and a degree of disintegration in the muscle fibers of all the fish examined were found.     

Ameliorative synergistic therapeutic effect of gallic acid and albendazole against Trichinella spiralis muscular phase infection and assessment of their effects on hepatic and cardiac tissues in male mice

Trichinellosis is a serious food-borne parasitic disease with serious community health effects, mainly causing muscle damage with no recent approved treatment. This study aimed to assess the therapeutic effect of gallic acid (GA) as a potent antioxidant against the encysted phase of Trichinella spiralis in male (BALB/c) mice alone or combined with albendazole (ALB) and to detect their synergistic effects on the histology and ultrastructure of skeletal and cardiac muscles and some biochemical blood analyses. Forty male mice were randomly divided into five groups (8 mice/group). 1^st group: the negative control received only distilled water, 2^nd group: the positive control (infected control group without treatment), 3^rd group: infected group plus treatment with ALB (50 mg Kg⁻¹ orally), and 4^th group: infected group and then treated with GA (30 mg Kg⁻¹ orally) and finally 5^th infected group treated with a combination of both ALB and GA. Aspartate and Alanine aminotransferase, Lactate dehydrogenase, alkaline phosphatase, C-reactive protein, Interleukin-4 and Creatine kinase were used as biochemical markers of hepatic and cardiac toxicity and inflammation. Malondialdehyde level, catalase, superoxide dismutase, and glutathione peroxidase were evaluated in heart tissue homogenates beside histological and ultra-structural examination of heart and skeletal muscles beside parasitological analyses. Results showed that the reduction % of Trichinella sp. larvae g⁻¹ in muscles of the group treated with the combination of GA and ALB showed overall reduction percentages. Oral administration of 30 mg kg¹ of GA led to infection reduction of T. spiralis than ALB treated group. Both administration of ALB beside GA showed the best treatment group that resulted in high infection reduction besides amelioration of both biochemical markers and restoration of histological and ultrastructures to normal state. In conclusion, GA is highly effective against T. spiralis which could be a promising alternative antioxidant drug and the GA effect was higher in the case of combination with ALB. This experiment provides a basis for further exploration of potent activities of other antioxidants against different phases of T. spiralis and the reduction of any health hazards prospectively.     

Cr3+,Cr6+及其复合污染对狐尾藻的毒害作用

采用急性毒害水培法,研究比较了不同浓度的Cr⁶⁺,Cr³⁺单一及复合处理对狐尾藻不定根和叶片生理生态的影响。实验结果表明:1)当浓度≤1mg·L^-1时,Cr³⁺对不定根的生长表现出促进作用,数量增加,长度增长。而Cr⁶⁺及复合处理系列对不定根却表现出强烈的抑制作用,在高浓度时甚至使其生长停止;2)叶绿素含量在1mg·L^-1Cr³⁺培养液中达到最大值,随Cr⁶⁺及复合处理浓度的增大而呈连续下降趋势;3)可溶性蛋白含量在三种处理方式中都表现出抛物线形式,复合处理组在1mg·L^-1时使蛋白含量出现高峰;4)细胞内超氧阴离子产生速率,膜脂过氧化水平与污染浓度和时间呈显著正相关;5)随着处理浓度的增加,SOD,OD,CAT活性先升后降,但其高峰分别出现在处理浓度为1mg·L^-1,10mg·L^-1,5mg·L^-1时;6)研究证实,Cr⁶⁺,Cr³⁺复合处理对狐尾藻的毒害作用较单一Cr⁶⁺,Cr³⁺显著,二者表现出协同作用,而其中Cr⁶⁺毒性大于Cr³⁺。     

Chelation therapy in intoxications with mercury,lead and copper

In the present review we provide an update of the appropriate use of chelating agents in the treatment of intoxications with compounds of mercury, lead and copper. The relatively new chelators meso-2,3-dimercaptosuccinic acid (DMSA) and 2,3-dimercapto-propanesulphonate (DMPS) can effectively mobilize deposits of mercury as well as of lead into the urine. These drugs can be administered orally and have relatively low toxicity compared to the classical antidote dimercaptopropanol (BAL). d-Penicillamine has been widely used in copper overload, although 2,3-dimercaptosuccinic acid or tetrathiomolybdate may be more suitable alternatives today. In copper-toxicity, a free radical scavenger might be recommended as adjuvant to the chelator therapy.     

Maternal cadmium exposure induces mt2 and smtB mRNA expression in zebrafish (Danio rerio) females and their offspring

The present study aimed to identify the effects of maternal cadmium (Cd(2+)) exposure on the mRNA expression of mt2 (metallothionein-2) and smtB (similar to metallothionein-B) in female zebrafish (Danio rerio) and their offspring (F1 larvae). Zebrafish females were exposed to 0, 8.9, 17.8, and 35.6 μM Cd(2+) for 72 h, and their ovaries and F1 larvae were collected to measure their Cd(2+) contents and their smtB and mt2 mRNA expression. Cd(2+) contents and the mRNA expression of smtB and mt2 in F1 larvae all showed positive correlations with the maternal Cd(2+) treatment dose. The mt2 was 1.9- to 3.4-fold higher than smtB in F1 larvae. Furthermore, F1 larvae had noticeably enhanced Cd(2+) tolerance after maternal Cd(2+) treatment. These results demonstrate that maternal Cd(2+) was transferred to larval fish and induced mt2 and smtB mRNA expression to protect larva against the impacts of Cd(2+). In female ovaries, mt2 expression showed a noticeable increase after exposure to a metal environment, while smtB did not show exactly the same effect. The study can only conclude that smtB might have a much different role other than just protecting against the impacts of metals.     

Reproductive kinetics of differentiating chondrocytes in normal states and in exposure to lead acetate

Parameters of the mitotic cycle of chondrocytes in the skeletal extremities of the rat foetuses were estimated in various experiments with 3H-thymidine. Lead acetate entering the organism during the gestation period influenced the mitotic cycle duration, increasing it at the expense of a presynthetic phase. A change in the proliferation rates delayed the bones' growth and affected the morphological structure of the forming epiphyseal cartilage.     

Prenatal stress reduces fertility of male offspring in mice, without affecting their adult testosterone levels

The male offspring of mice stressed by crowding during the final third of pregnancy showed reductions in sexual behavior and fertility. When paired with receptive females, their latencies to mount and to achieve intromission and ejaculation were greater than controls, and 30% of them failed to ejaculate in the 100-min test. When housed continuously for 4 days with females, 31% of them failed to impregnate their partners, compared with 4% of controls. The sexual receptivity of the untreated females paired with prenatally stressed males was not affected. Resting testosterone levels of prenatally stressed males did not differ from those of controls, and the pattern of rise and fall of testosterone during a 60-min interaction with a female showed only minor differences. The results suggest a central, rather than peripheral, mediation of the behavioral effects of prenatal stress.     

Preliminary studies on the ability of plant barriers to capture lead and cadmium of vehicular origin

The purpose of this study is to determine the type of plant barrier most suitable for the protection of areas adjacent to roadways from the emissions of motor vehicles, as well as to establish the most efficient plant species for use in the barriers. The survey gathered the following samples: (a) grass and soil samples near the major Italian motorway networks and from sites directly exposed to vehicle emissions or protected by plant barriers; (b) samples of leaves from various species of trees, growing both alongside motorways and in urban and remote sites. The results show that the most efficient barriers are those placed immediately alongside the road edge and the most efficient species are deciduous broadleaves and small-needle conifers.