Glutamine Defended the Kidneys Versus Lead Intoxication Via Elevating Endogenous Antioxidants, Reducing Inflammation and Carbonyl Stress, as well as Improving Insulin Resistance and Dyslipidemia

Kidneys are primarily sensitive to lead (Pb) poisoning due to their cardinal role in lead excretion. Then, we studied the effect of glutamine (Gln) on lead nephrotoxicity in rats by assessing the histopathological and biochemical parameters (the renal NF-kβ expression, metabolic profile, oxidative stress, inflammatory markers, methylglyoxal (MGO), and glyoxalase-I activity). Forty rats were allotted into four groups (ten rats in each): normal (N), Gln-treated N, Pb intoxication (Pbi), and Gln-treated Pbi. The treated groups took 0.1% Gln in drinking water for 1 month. To motivate lead poisoning, rats gained 50 mg/l lead acetate in drinking water for 1 month. Oxidative stress indices (total glutathione, its reduced and oxidized forms, their ratios, advanced protein oxidation products, malondialdehyde, and ferric ion reducing power) and inflammatory markers (renal nuclear factor-kβ expression, interleukin 1β level, and myeloperoxidase activity) were measured. Furthermore, metabolic profile (fasting blood sugar, insulin, insulin resistance, lipid profile, and atherogenic index) and renal dysfunction parameters were determined. Pb-induced renal histopathological alterations were investigated by a pathologist. In the kidney of Pbi rats, the glomerulus was damaged. Gln prevented kidney damage and reduced kidney dysfunction parameters. In addition, Gln decreased oxidative stress and inflammation in sera and kidney homogenates. In addition, it improved insulin resistance, dyslipidemia, and carbonyl stress (p < 0.001). Gln guarded the kidneys versus lead intoxication by improving insulin resistance and dyslipidemia, elevating antioxidant markers, and diminishing inflammation and carbonyl stress.

Chronic lead poisoning-induced budgerigar liver damage, gut microbiota dysbiosis, and metabolic disorder

Birds are sensitive to heavy metal pollution, and lead (Pb) contamination can negatively affect their liver and gut. Therefore, we used budgerigars to examine liver and gut toxicosis caused by Pb exposure in bird, and the possible toxic mechanisms. The findings showed Pb exposure increased liver weight and decreased body weight. Moreover, histopathological and immunofluorescence assay results demonstrated obvious liver damage and cell apoptosis increased in Pb- treated budgerigars. Quantitative polymerase chain reaction (qPCR) results also showed Pb caused an increase in apoptosis by inhibiting the PPAR-γ/PI3K/Akt pathway. The gut microbe analyses indicated Firmicutes, Proteobacteria, and Bacteroidetes were dominant microbial phyla, and Network analysis results shown Arthrobacter, Bradyrhizobium and Alloprevotella as the hubs of Modules I, II, and III, respectively. Phenylpropanoids and polyketides, Organoheterocyclic compounds, Organic oxygen compounds, and Organic nitrogen compounds were dominant metabolite superclasses. Tauroursodeoxycholic acid, taurochenodeoxycholic acid (sodium salt), and 2-[2-(5-bromo-2-pyridyl)diaz-1-enyl]-5-(diethylamino)phenol were significantly enriched in the Pb-treated group. It showed that 41 Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologues and 183 pathways differed between the Pb-treated and control budgerigars using microbial and metabolomic data. Moreover, orthogonal partial least-squares discrimination analysis (OPLS-DA) based on microbial and metabolite indicated distinct clusters in the Pb-treated and control groups. Additionally, the correlation analysis results indicated that a positive correlation for the Pb-treated and control groups between gut microbiota and metabolomic data, respectively. Furthermore, the microenvironment of the gut and liver were found to affect each other, and this study demonstrated heavy metal especially Pb may pose serious health risks to birds through the "gut-liver axis" too.

Trend in blood lead levels in Taiwanese adults 2005-2017

This study examined the trend of blood lead levels (BLLs) in Taiwanese adults and analyzed the variations in the BLL between Linkou (northern) and Kaohsiung (southern) hospital branches. Between 2005 and 2017, 3,804 adult participants received blood lead tests at the Linkou (n = 2,674) and Kaohsiung (n = 1,130) branches of Chang Gung Memorial Hospital. The geometric mean of BLL was 2.77 μg/dL. The adult participants from the Kaohsiung branch were not only age older (49.8±14.1 versus 39.4±14.2 years; P<0.001) and male predominant (65.8 versus 41.7%; P<0.001) but also showed a higher BLL (4.45±3.93 versus 2.82±2.42 μg/dL; P<0.001) and lower estimated glomerular filtration rate (87.62±25.94 versus 93.67±23.88; P<0.001) than those from the Linkou branch. Multivariable logistic regression analysis revealed that the Kaohsiung branch [odds ratio (OR): 7.143; 95% confident interval (CI): 5.682–8.929; P<0.001], older age (OR: 1.008; 95% CI: 1.000–1.015; P = 0.043) and reduced estimated glomerular filtration rate (OR: 1.009; 95% CI: 1.004–1.014; P = 0.001) were significant predictors for BLL > 5 μg/dL. Therefore, this study confirmed a continuous decreasing trend in the BLL in Taiwan after banning leaded petrol in 2000.

The impact of chicory (Cichoriumintybus L.) on hemodynamic functions and oxidative stress in cardiac toxicity induced by lead oxide nanoparticles in male rats

BACKGROUND

A common environmental pollutant, lead can induce toxicity in several organ systems. A range of industrial and/or household materials and products contain lead, and food/liquid ingestion and inhalation are the mechanisms through which lead is introduced into the human body.

OBJECTIVE

Since knowledge about the cardiac toxicity of acute lead nanoparticles is limited, this work sought to shed more light on the issue by investigating the therapeutic effects of chicory extract based on rat models to elevate cardiac functions and oxidative stress.

METHODS

Four research groups were used, each consisting of ten albino rats of male sex and adult age. The groups were: control group, chicory group, lead oxide nanoparticle group, and lead oxide nanoparticle + chicory group.

RESULTS

Compared to the control and chicory groups, the lead oxide nanoparticle group displayed a notable increase in heart functions and oxidative stress markers as well as alterations in cardiac histological structure. On the other hand, cardiac function modifications were counteracted through four-week administration of lead oxide nanoparticles alongside chicory.

CONCLUSION

Heart damage caused by lead oxide nanoparticles may be attenuated by chicory through scavenging of free radicals.

Ginseng Gintonin Attenuates Lead-Induced Rat Cerebellar Impairments during Gestation and Lactation

Gintonin, a novel ginseng-derived lysophosphatidic acid receptor ligand, improves brain functions and protects neurons from oxidative stress. However, little is known about the effects of gintonin against Pb-induced brain maldevelopment. We investigated the protective effects of gintonin on the developing cerebellum after prenatal and postnatal Pb exposure. Pregnant female rats were randomly divided into three groups: control, Pb (0.3% Pb acetate in drinking water), and Pb plus gintonin (100 mg/kg, p.o.). Blood Pb was increased in dams and pups; gintonin treatment significantly decreased blood Pb. On postnatal day 21, the number of degenerating Purkinje cells was remarkably increased while the number of calbindin-, GAD67-, NMDAR1-, LPAR1-immunoreactive intact Purkinje cells, and GABA transporter 1-immunoreactive pinceau structures were significantly reduced in Pb-exposed offspring. Following Pb exposure, gintonin ameliorated cerebellar degenerative effects, restored increased pro-apoptotic Bax, and decreased anti-apoptotic Bcl2. Gintonin treatment attenuated Pb-induced accumulation of oxidative stress (Nrf2 and Mn-SOD) and inflammation (IL-1β and TNFα,), restoring the decreased cerebellar BDNF and Sirt1. Gintonin ameliorated Pb-induced impairment of myelin basic protein-immunoreactive myelinated fibers of Purkinje cells. Gintonin attenuated Pb-induced locomotor dysfunctions. The present study revealed the ameliorating effects of gintonin against Pb, suggesting the potential use of gintonin as a preventive agent in Pb poisoning during pregnancy and lactation.

Outbreak investigation of lead neurotoxicity in children from artificial jewelry cottage industry

BACKGROUND

Although lead neurotoxicity is a known phenomenon, it can often be missed at a primary or secondary care level especially if detailed environmental exposure history is missed.

METHODS

This is an outbreak investigation where we observed 15 pediatric cases with neurologic signs and symptoms clustered in a slum area known for an unorganized artificial jewelry industry. Their clinical, biochemical, and epidemiological features were compared with 14 other children from the same region reporting with non-neurological symptoms who were considered as unmatched controls.

RESULTS

Cases with neurological manifestations had a higher in-house lead smelting activity [OR 7.2 (95% CI 1.4-38.3)] as compared to controls. Toddlers below 3 years of age were more vulnerable to the effects of lead.

CONCLUSION

This study emphasizes that many focal sources of lead poisoning still remain especially in the unorganized sector. In cases presenting with unexplained neurotoxicity, specific occupational and environmental inquiry for chemical poisoning, with special consideration for lead, should be actively pursued.

Effect of Zingiber officinale on some biochemical parameters and cytogenic analysis in lead-induced toxicity in experimental rats

Exposure to toxic elements is greatly unavoidable in our daily activities due to several routes of coming in contact with these elements. Thus lead (Pb), is one of the major causes of health hazard in human. In this study, evaluation of Zingiber officinale as mitigating measure against Pb induced biochemical and cytogenic toxicity in albino rats was investigated. Experimental rats were grouped into five with five animals per group, group I serves as control and groups 2-5 were induced intraperitoneal with lead acetate dissolved in distilled water at 3 mg/kg body weight whereas group 3-5 were orally administered with 200 mg/kg vitamin C, 200 mg/kg, and 100 mg/kg of Z. officinale, respectively for 7 d. The obtained results show that aspartate aminotransferase (AST), alkaline phosphatase (ALP), lipid peroxidation, urea, creatinine, bilirubin, and gamma-glutamyl transferase (GGT) were significantly increased (p < 0.05) and catalase (CAT) were reduced progressively in Pb alone induced rats. Hematological parameters showed a progressive reduction (p < 0.05) in lead acetate alone rats. There were significant changes in micronuclei (MN), chromosomal aberrations (CA) frequency, and oxidative damages in the bone marrow cells from lead acetate alone induced rats, although, mitotic index scores in these cells were reduced gradually (p < 0.05). The altered parameters were significantly reversed toward the levels observed in normal control rats administered with vitamin C and aqueous extract of Z. officinale. Hence, these results suggest that Z. officinale roots might contain therapeutic potential that can ameliorate the hazard effect of lead acetate poison.

Participation of phospholipase-A2 and sphingomyelinase in the molecular pathways to eryptosis induced by oxidative stress in lead-exposed workers

The increment of eryptosis in lead-exposed workers has been associated with oxidative stress, having as the main mediator [Ca²⁺]_i. However, other molecules could participate as signals, such as PLA₂ and SMase, which have been proposed to increase PGE₂ and ceramides, both involved in the increment of PS externalization due to osmotic stress. To study the role of these enzymes in lead intoxication, we studied 30 lead exposed workers and 27 non-lead exposed individuals. We found, compared to non-exposed subjects, lead intoxication characterized by high blood lead concentration (median = 39.1 μg/dL), and low δ-ALAD activity (median = 348 nmol of porphobilinogen/h/mL); oxidative stress with high lipid peroxidation (median = 1.31 nmol of malondialdehyde/mL) and low TAC (median = 370 mM Trolox equivalents); a higher enzymatic activity of PLA₂ (median = 518 AFU/mg) and SMase (median = 706 AFU/mg) and higher eryptosis (median = 0.92% PS externalization). Correlation and conditional probability analyses permit to associate oxidative stress and eryptosis with high PLA₂ activity. However, high SMase activity was only associated with PLA₂ activity. The role of these enzymes in the signal path to eryptosis induced by oxidative stress in lead-exposed workers is discussed.

Effects of short term lead exposure on gut microbiota and hepatic metabolism in adult zebrafish

Lead (Pb) is one of the most prevalent toxic, nonessential heavy metals that has been associated with a wide range of toxic effects in humans and environmental animals. Here, effects of short time exposure to 10 and 30 μg/L Pb on gut microbiota and hepatic metabolism were analyzed in adult male zebrafish. We observed that both 10 and 30 μg/L Pb increased the volume of mucus in the gut. At phylum level, the abundance of α-Proteobacteria decreased significantly and the abundance of Firmicutes increased significantly in the gut when treated with 30 μg/L Pb for 7 days. In addition, the 16S rRNA gene sequencing for V3-V4 region revealed a significant change in the richness and diversity of gut microbiota in 30 μg/L Pb exposed group. A more depth analysis, at the genus level, discovered that 52 gut microbes identified by operational taxonomic unit analysis were changed significantly in 30 μg/L Pb treated group. Based on GC/MS metabolomics analysis, a total of 41 metabolites were significantly altered in 30 μg/L Pb treatment group. These changed metabolites were mainly associated with the pathways of glucose and lipid metabolism, amino acid metabolism, nucleotide metabolism. In addition, we also confirmed that the transcription of some genes related to glycolysis and lipid metabolism, including Gk, Aco, Acc1, Fas, Apo and Dgat, decreased significantly in the liver of zebrafish when exposed to 30 μg/L Pb for 7 days. Our results observed that Pb could cause gut microbiota dysbiosis and hepatic metabolic disorder in zebrafish.

Lead-induced changes of cytoskeletal protein is involved in the pathological basis in mice brain

Lead poisoning is a geochemical disease. On the other hand, lead is highly carcinogenic and exhibits liver and kidney toxicity. This element can also cross the blood-brain barrier, reduce learning and memory ability and damage the structure of the cerebral cortex and hippocampus. To further investigate the mechanism of lead neurotoxicity, 4-week-old Kunming mice were used to explore the effects of different concentrations of Pb²⁺ (0, 2.4, 4.8 and 9.6 mM) for 9 days. In this study, pathological and ultrastructural changes in brain cells of the treated group were related to damages to mitochondria, chromatin and the nucleus. Lead content in blood was tested by atomic absorption spectroscopy, which showed high lead concentrations in the blood with increasing doses of lead. Distribution of lead in nerve cells was analysed by transmission electron microscopy with energy dispersive spectroscopy. Data showed the presence of lead in nucleopores, chromatin and nuclear membrane of nerve cells in the treatment groups, whereas lead content increased with increasing doses of lead acetate. Finally, microtubule-associated protein 2 (MAP2) mRNA and protein expression levels were detected by real-time PCR and Western blotting, which showed a reduction in MAP2 expression with increasing lead doses in the mouse brain. These findings suggest that acute lead poisoning can cause significant dose-dependent toxic effects on mouse brain function and can contribute to better understanding of lead-induced toxicity.

Role of geraniol against lead acetate-mediated hepatic damage and their interaction with liver carboxylesterase activity in rats

In this study, the effect of geraniol (50 mg/kg for 30 d), a natural antioxidant and repellent/antifeedant monoterpene, in a rat model of lead acetate-induced (500 ppm for 30 d) liver damage was evaluated. Hepatic malondialdehyde increased in the lead acetate group. Reduced glutathione unchanged, but glutathione S-transferase, glutathione reductase, as well as carboxylesterase activities decreased in geraniol, lead acetate and geraniol + lead acetate groups. 8-OhDG immunoreactivity, mononuclear cell infiltrations and hepatic lead concentration were lower in the geraniol + lead acetate group than the lead acetate group. Serum aspartate aminotransferase and alanine aminotransferase activities increased in the Pb acetate group. In conclusion, lead acetate causes oxidative and toxic damage in the liver and this effect can reduce with geraniol treatment. However, we first observed that lead acetate, as well as geraniol, can affect liver carboxylesterase activity.

The Bioinorganic Chemistry of Lead in the Context of Its Toxicity

Owing to its abundance on earth and its multiple uses by humans, lead (Pb) is a major toxicant that has threatened human health for millennia and continues to do so. There is no safe level of exposure, necessitating a nuanced approach to its control in the food we consume, the water we drink, and the air we breathe. Turnover in soft tissues is within days. In contrast, lead accumulates in bone and turns over with a half-life of about 30 years, though it can be mobilized from bone under physiological and pathophysiological conditions of bone resorption. Children are particularly vulnerable to lead exposure and suffer irreversible neurological deficits affecting learning ability and behavior. In adults, chronic effects of exposure to lead include elevated blood pressure, development of cancers, and, as suggested more recently, neurodegeneration. Some pathways of systemic and cellular metabolism of Pb(II) are known. However, except for its action in δ-aminolevulinate dehydratase, its molecular toxicology remains largely speculative in terms of specific targets. One major molecular mechanism seems to be the replacement of zinc with lead in zinc proteins with functional consequences. Calcium binding proteins are also being discussed as possible targets. However, the affinities of lead for calcium sites in proteins are orders of magnitude lower than those for zinc sites. Therefore, it remains to be shown whether lead at the concentrations occurring in tissues can replace calcium in proteins in vivo. Despite humans having recognized the hazards of lead exposure for a very long time, uncertainties remain as to the threshold for adverse effects on our health and the low levels of exposure during our lives as a risk factor for chronic disease.

Toxicology of Lead and Its Damage to Mammalian Organs

The toxicity of lead has been appreciated for centuries. Lead is a commonly used metal in industrialized nations, which results in the release of lead into the environment. Governmental agencies regulate the amount of lead permissible for workers to be exposed to; however, unregulated environmental lead exposure is a high concern. While essential metals have physiologic roles, there are no health benefits from lead intake. In this chapter, we discuss sources of lead exposure, the absorption, distribution, and elimination of lead from the human body, and molecular mechanisms of lead-induced toxicity. We also discuss the evidence on the association between lead exposure and blood pressure, and the influence of sociodemographic, lifestyle and environmental determinants of lead exposure in the general population. We highlight the effects on the nervous system, kidney, immune system, blood, reproductive system, and bones.

Gamma-Glutamyl Cysteine Attenuates Tissue Damage and Enhances Tissue Regeneration in a rat Model of Lead-Induced Nephrotoxicity

Lead is a biohazardous metal that is commonly involved in human illness including renal injury. Although it is a non-redox reactive metal, lead-induced renal injury is largely based on oxidative stress. The current work aimed at exploring the possible protective effect of γ-glutamyl cysteine (γGC) against lead-induced renal injury. Rats were allocated to normal and γGC control groups, lead-treated group, and lead and γGC-treated group. γGC alleviated lead-induced renal injury as evidenced by attenuation of histopathological aberration, amelioration of oxidative injury as demonstrated by significant reduction in lipid and protein oxidation, elevation of total antioxidant capacity, and glutathione level. The activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) was significantly elevated. γGC significantly decreased levels of the proinflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β and the activity of the apoptotic marker caspase-3. In addition, γGC reduced kidney lead content, enhanced weight gain, and improved renal function as demonstrated by reduced serum levels of urea and creatinine. Importantly, γGC upregulated proliferating cell nuclear antigen (PCNA) expression, denoting enhanced renal regenerative capacity. Together, our findings highlight evidence for alleviating effects of γGC against lead-induced renal injury that is potentially mediated through diminution of oxidative tissue injury, reduction of inflammatory response, attenuation of apoptosis, and enhancement of renal regenerative capacity.

Clastogenic but Not Apoptotic Effects on Human Artery Endothelial Cells by Concentrations of Inorganic Lead Inhibiting Their Nitric Oxide Production

Human coronary artery endothelial cells (HCAEC 5156) were cultured as monolayers and exposed to concentrations of lead (as acetate, Pb) in the culture medium similar or lower than those commonly found in the blood of human beings occupationally or environmentally exposed to this element. Only at the concentration of 200 ng/mL, Pb reduced growth rate of HCAEC 5156 cells starting from the 3rd day and up to the 5th day of incubation. On the other hand, Pb (0.2, 2 and 200 ng/mL) increased concentration-dependently micronuclei formation in binucleated HCAEC5156 cells, as it was shown by the cytokinesis-blocked micronucleus assay (CBMN assay) carried out after 48 hours of exposure to the metal. However, Pb was unable, at all the above concentrations, to induce apoptosis in HCAEC 5156 cells following a 48 hour-exposure, as shown by an electrophoretic apoptotic DNA fragmentation test. Moreover, Pb (2 and 200 ng/mL) reduced significantly the concentration of nitric oxide (NO, determined analytically as L-citrulline) in both culture medium and cytosol of HCAEC 5156 cells following a 7 day-exposure to the element. Results were discussed also in relation to evidences of other studies reporting genotoxic and/or apoptotic effects of Pb on various cell types at very elevated dosages or concentrations. The observed clastogenic effects of Pb were explained through a series of mechanisms involving interactions between oxygen reactive species and NO and/or reduced NO synthesis in the endothelium, thus leading to a depressed NO bioavailability. This research first shows that Pb is provided with clastogenic but not apoptotic effects on cultured human endothelial cells. It was emphasized that such effects are induced by Pb concentrations similar to those commonly found in blood and tissues of laboratory animals showing Pb induced cardiovascular and/or neuropsychological alterations.

Water Spinach, Ipomoea aquatic (Convolvulaceae), Ameliorates Lead Toxicity by Inhibiting Oxidative Stress and Apoptosis

BACKGROUND

Ipomoea aquatica (Convolvulaceae), an aquatic edible plant, is traditionally used against heavy metal toxicity in India. The current study intended to explore the protective role of edible (aqueous) extract of I. aquatica (AEIA) against experimentally induced Pb-intoxication.

METHODS

The cytoprotective role of AEIA was measured on mouse hepatocytes by cell viability assay followed by Hoechst staining and flow cytometric assay. The effect on ROS production, lipid peroxidation, protein carbonylation, intracellular redox status were measured after incubating the hepatocytes with Pb-acetate (6.8 μM) along with AEIA (400 μg/ml). The effects on the expressions of apoptotic signal proteins were estimated by western blotting. The protective role of AEIA was measured by in vivo assay in mice. Haematological, serum biochemical, tissue redox status, Pb bioaccumulation and histological parameters were evaluated to estimate the protective role of AEIA (100 mg/kg) against Pb-acetate (5 mg/kg) intoxication.

RESULTS

Pb-acetate treated hepatocytes showed a gradual reduction of cell viability dose-dependently with an IC50 value of 6.8 μM. Pb-acetate treated hepatocytes exhibited significantly enhanced levels (p < 0.01) of ROS production, lipid peroxidation, protein carbonylation with concomitant depletion (p < 0.01) of antioxidant enzymes and GSH. However, AEIA treatment could significantly restore the aforementioned parameters in murine hepatocytes near to normalcy. Besides, AEIA significantly reversed (p < 0.05-0.01) the alterations of transcription levels of apoptotic proteins viz. Bcl 2, Bad, Cyt C, Apaf-1, cleaved caspases [caspase 3, caspase 8 and caspase 9], Fas and Bid. In in vivo bioassay, Pb-acetate treatment caused significantly high intracellular Pb burden and oxidative pressure in the kidney, liver, heart, brain and testes in mice. In addition, the haematological and serum biochemical factors were changed significantly in Pb-acetate-treated animals. AEIA treatment restored significantly the evaluated-parameters to the near-normal position.

CONCLUSION

The extract may offer the protective effect via counteracting with Pb mediated oxidative stress and/or promoting the elimination of Pb by chelating. The presence of substantial quantities of flavonoids, phenolics and saponins would be responsible for the overall protective effect.

Lead Poisoning Disturbs Oligodendrocytes Differentiation Involved in Decreased Expression of NCX3 Inducing Intracellular Calcium Overload

Lead (Pb) poisoning has always been a serious health concern, as it permanently damages the central nervous system. Chronic Pb accumulation in the human body disturbs oligodendrocytes (OLs) differentiation, resulting in dysmyelination, but the molecular mechanism remains unknown. In this study, Pb at 1 μM inhibits OLs precursor cells (OPCs) differentiation via decreasing the expression of Olig 2, CNPase proteins in vitro. Moreover, Pb treatment inhibits the sodium/calcium exchanger 3 (NCX3) mRNA expression, one of the major means of calcium (Ca²⁺) extrusion at the plasma membrane during OPCs differentiation. Also addition of KB-R7943, NCX3 inhibitor, to simulate Pb toxicity, resulted in decreased myelin basic protein (MBP) expression and cell branching. Ca²⁺ response trace with Pb and KB-R7943 treatment did not drop down in the same recovery time as the control, which elevated intracellular Ca²⁺ concentration reducing MBP expression. In contrast, over-expression of NCX3 in Pb exposed OPCs displayed significant increase MBP fluorescence signal in positive regions and CNPase expression, which recovered OPCs differentiation to counterbalance Pb toxicity. In conclusion, Pb exposure disturbs OLs differentiation via affecting the function of NCX3 by inducing intracellular calcium overload.

Ameliorative potential of stem bromelain on lead-induced toxicity in Wistar rats

The present study investigates the protective efficacy of stem bromelain against lead-induced toxicity in male Wistar rats. There were six experimental groups; Group I was negative control, Group II was administered only 20 mg/kg of stem bromelain. Group III and V were orally exposed to 30 mg/kg/day and 60 mg/kg/day of lead acetate, respectively. Group IV and Group VI were exposed to both low and high dose of lead acetate, respectively, and treated with 20 mg/kg stem bromelain. The experimental period was 21 days. The end points evaluated were, lead accumulation in kidney, liver and spleen, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity, serum malonaldehyde (MDA) cholesterol and triglycerides levels. Co-administration of stem bromelain with lead markedly reduced the lead accumulation in the kidney and spleen. The treatment of stem bromelain also reduced the serum MDA levels in the group exposed to lower dose of lead and serum triglyceride level in the group exposed to higher dose of lead. The lead-induced modulated levels of serum ALT and AST were also alleviated by bromelain treatment. Our key findings suggest a chelating potential of stem bromelain for combating lead toxicity and oxidative stress. Bromelain represents a novel approach to the treatment of metal toxicity and metabolic disorders with a limited therapeutic window.

Dysplastic changes in erythroid precursors as a manifestation of lead poisoning: report of a case and review of literature

Dysplastic changes in erythroid precursors occur not only in patients with hematologic diseases, but also those with other diseases. Here, we report on a patient that presented with dysplastic changes in erythroid precursors due to lead poisoning from the intake of Chinese folk remedies.

Long-term ultrastructural indices of lead intoxication in pulmonary tissue of the rat

In the present research long-term pulmonary toxicity of lead was investigated in rats treated by intraperitoneal administration of lead acetate for three consecutive days (25 mg/kg per day). Five weeks after treatment average lead content in the whole blood was 0.41 μg/dL ± 0.05, in the lung homogenates it measured 3.35 μg/g ± 0.54, as compared to the control values of 0.13 ± 0.07 μg/dL and 1.03 μg/g ± 0.59, respectively. X-ray microanalysis of lung specimens displayed lead localized mainly within type II pneumocytes and macrophages. At the ultrastructural level the effects of lead toxicity were found in lung capillaries, interstitium, epithelial cells, and alveolar lining. Alveolar septa showed intense fibrosis, consisting of collagen, elastin, and fibroblasts. Thinned alveolar septa had emphysematous tissue with some revealing signs of angiogenesis. Type II pneumocytes contained lamellar bodies with features of laminar destruction. Fragments of the surfactant layer were often detached from the alveolar epithelium. These findings indicate that 5 weeks after exposure, lead provokes reconstruction of the alveolar septa including fibrosis and emphysematous changes in the lung tissue.

Protective effect of artichoke (Cynara scolymus) leaf extract against lead toxicity in rat

CONTEXT

Artichoke, Cynara scolymus L. (Asteraceae), has many natural antioxidants and multiple pharmacological actions. Recent studies have shown that it has antitoxic activity.

OBJECTIVE

Lead (Pb) is a dangerous environmental toxicant that induces a broad range of dysfunctions in human. This study evaluated the protective effect of the hydroethanolic extract of artichoke against altered biochemical parameters in rats fed with lead-containing diet.

MATERIALS AND METHODS

Thirty-two rats were randomly divided into four groups. The first (control) group received standard diet. The second, third and fourth groups received 500 mg lead/kg diet, 500 mg lead/kg diet plus 300 mg/kg b.w. artichoke extract daily, and 500 mg lead/kg diet plus 1 mg vitamin C/100 g b.w. daily for 6 weeks, respectively. Serum lead, lipoprotein profile, ALT (alanine transaminase), AST (aspartate transaminase), ALP (alkaline phosphatase), malondialdehyde (MDA) and liver histopathology assessments were conducted.

RESULTS

Serum lead, triglyceride (TG), VLDL, ALT, AST, ALP and MDA levels decreased significantly (p < 0.05) in the artichoke-treated group (35.85, 38.26, 38.38, 21.90, 12.81, 26.86 and 46.91%, respectively) compared to lead-intoxicated rats without treatment. No significant change was observed in serum lead, ALP and ALT between artichoke and vitamin C-treated groups (p > 0.05). Furthermore, the liver histopathology in rats treated with artichoke showed a mild degree of lymphocyte infiltration that was relatively comparable to the control and vitamin C-treated groups.

DISCUSSION AND CONCLUSION

These results clearly show that the artichoke extract in lead-poisoned rats has suitable chelating properties for the reduction of blood lead levels.