Impact of heavy metal pollution on the hemogram and serum biochemistry of the Libyan jird, Meriones libycus

Joint and interactive effects of metal mixtures on liver damage: Epidemiological evidence from repeated-measures study

BACKGROUND

The impact of heavy metals on liver function has been examined in numerous epidemiological studies. However, these findings lack consistency and longitudinal validation.

METHODS

In this study, we conducted three follow-up surveys with 426 participants from Northeast China. Blood and urine samples were collected, along with questionnaire information. Urine samples were analyzed for concentrations of four metals (chromium [Cr], cadmium [Cd], lead [Pb], and manganese [Mn]), while blood samples were used to measure five liver function indicators (alanine aminotransferase [ALT], aspartate aminotransferase [AST], albumin [ALB], globulin [GLB], and total protein [TP]). We utilized a linear mixed-effects model (LME) to explore the association between individual heavy metal exposure and liver function. Joint effects of metal mixtures were investigated using quantile g-computation and Bayesian kernel machine regression (BKMR). Furthermore, we employed BKMR and Marginal Effect models to examine the interaction effects between metals on liver function.

RESULTS

The LME results demonstrated a significant association between urinary heavy metals (Cr, Cd, Pb, and Mn) and liver function markers. BKMR results indicated positive associations between heavy metal mixtures and ALT, AST, and GLB, and negative associations with ALB and TP, which were consistent with the g-comp results. Synergistic effects were observed between Cd-Cr on ALT, Mn-Cr and Cr-Pb on ALB, while an antagonistic effect was found between Mn-Pb and Mn-Cd on ALB. Additionally, synergistic effects were observed between Mn-Cr on GLB and Cd-Cr on TP. Furthermore, a three-way antagonistic effect of Mn-Pb-Cr on ALB was identified.

CONCLUSION

Exposure to heavy metals (Cr, Cd, Mn, Pb) is associated with liver function markers, potentially leading to liver damage. Moreover, there are joint and interaction effects among these metals, which warrant further investigation at both the population and mechanistic levels.

Protective effect of Agaricus bisporus mushroom against maternal and fetal damage induced by lead administration during pregnancy in rats

INTRODUCTION

Lead (Pb) is a toxic pollutant, which can affect different tissues of the human body. The use of natural elements, as medicinal mushroom can reduce the toxic effects of Pb.

OBJECTIVE

We evaluated, through preclinical tests, the oral co exposures to mushroom Agaricus bisporus (Ab) by gavage and Pb in drinking water, and the capability of Ab be a protective agent for both pregnant rats and their fetuses.

METHODS

Female Wistar rats were divided into four groups (n = 5/group): Group I-Control; Group II-Ab 100 mg/kg; Group III-Pb 100 mg/L; Group IV-Ab +Pb -100 mg/kg +100 mg/L. Exposure was performed until the 19th day of gestation. On the 20th day, pregnant rats were euthanized, and the outcomes evaluated were weight gain; hematological profile; biochemical markers; oxidative stress markers; reproductive capacity; and embryo fetal development.

RESULTS

The characterization of mushrooms reveals them to be a valuable source of nutrients. However, Pb ingestion resulted in reduced weight gain and negative impacts on hematological and biochemical parameters. Fortunately, co administration of mushrooms helped to mitigate these negative effects and promote recovery. The mushroom also showed antioxidant activity, improving parameters of oxidative stress. In addition, Ab partially recovered the damage in fetal morphology and bone parameters.

CONCLUSION

Our findings indicated that the co administration of Ab improved the toxicity caused by Pb, and the mushroom could be used as a natural alternative as a protective/chelator agent.

Assessment for the associations of twenty-three metal(loid)s exposures with early cardiovascular damage among Chinese urban adults with five statistical methods: Insight into assessing health effect of multipollutant exposure

The topic of cardiovascular hazards from multiple metal (loid)s exposures has attracted widespread attention. Here, we measured concentrations of twenty-three urinary metal (loid)s and mean platelet volume (MPV), an early cardiovascular damage biomarker, for 3396 Chinese adults. We aimed to comprehensively assess the associations of single metal (loid) and multiple metal (loid)s (as a mixture) with MPV by combined use of five statistical methods, including general linear models, Bayesian kernel machine regression (BKMR), weight quartile sum (WQS) regression, quantile g-computation (QGC), and adaptive elastic network regression (AENR). And based on that, we hope to provide insight into assessing the health effect of multipollutant exposure. After adjustment for potential covariates, at least three methods jointly suggested that of twenty-three metal (loid)s, iron, arsenic, and antimony were positively while aluminum, tungsten, and thallium were inversely associated with MPV. The environmental risk score of metal (loid)s construed by AENR was significantly positively associated with MPV, while the association between overall twenty-three metal (loid)s mixture and MPV was neutralized to be insignificant in QGC and BKMR. Conclusively, single metal (loid) may be inversely (iron, arsenic, and antimony) and positively (aluminum, tungsten, and thallium) associated with early cardiovascular damage, while the association of overall twenty-three metal (loid)s mixture with MPV was insignificant when concurrent exposures exist. It is crucial to select appropriate statistical methods based on study purpose and principles/characteristics of statistical methods, and combined employment of multimethod is insightfully suggested when assessing health effects of multipollutant exposure.

Associations between Individual Exposure to Fine Particulate Matter Elemental Constituent Mixtures and Blood Lipid Profiles: A Panel Study in Chinese People Aged 60-69 Years

Dyslipidemia may be a potential mechanism linking fine particulate matter (PM_2.5) to adverse cardiovascular outcomes. However, inconsistent associations between PM_2.5 and blood lipids have resulted from the existing research, and the joint effect of PM_2.5 elemental constituents on blood lipid profiles remains unclear. We aimed to explore the overall associations between PM_2.5 elemental constituents and blood lipid profiles and to identify the significant PM_2.5 elemental constituents in this association. Sixty-nine elderly people were recruited between September 2018 and January 2019. Each participant completed a survey questionnaire, 3 days of individual exposure monitoring, health examination, and biological sample collection at each follow-up visit. Bayesian kernel machine regression (BKMR) models were used to identify the joint effects of the 17 elemental constituents on blood lipid profiles. Total cholesterol, low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (non-HDL-C) levels were significantly increased in older adults when exposed to the mixture of PM_2.5 elemental constituents. Copper and titanium had higher posterior inclusion probabilities than other constituents, ranging from 0.76 to 0.90 (Cu) and 0.74 to 0.94 (Ti). Copper and titanium in the PM_2.5 elemental constituent mixture played an essential role in changes to blood lipid levels. This study highlights the importance of identifying critical hazardous PM_2.5 constituents that may cause adverse cardiovascular outcomes in the future.

Evaluation of the Effects of Nitrilotriacetic Acid as a Chelating Agent on the Biochemical Toxicity of Lead in Oreochromis niloticus

In the present research, the effects of sublethal lead (Pb) concentrations on total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) levels, enzyme activities (aspartate transaminase, AST; alanine transaminase, ALT; lactate dehydrogenase, LDH), ion levels (magnesium, Mg; sodium, Na; potassium, K; chlorine, Cl; calcium, Ca), and some metabolite levels (cholesterol, triglyceride, HDL, LDL, albumin, total protein) in the blood serum of Oreochromis niloticus and the protective function of nitrilotriacetic acid (NTA) due to its chelating characteristic were investigated. O. niloticus, which has an important position in the food chain and is often preferred in toxicological studies, was exposed to 0.1 ppm Pb, 0.1 ppm Pb + 0.3 ppm NTA, 1 ppm Pb, and 1 ppm Pb + 3 ppm NTA concentrations for 7 and 21 days. At the end of the duration, serum TAS and TOS levels were measured spectrophotometrically with Rel Assay Diagnostics; other enzyme activities, ion levels, and metabolite parameters were done by an autoanalyzer using commercial kits. Depending on the exposure periods and concentrations, the changes in the parameters were determined. It is determined that, under the influence of high ambient concentration of lead, TOS, OSI, AST, ALT, LDH, LDL, triglyceride, and Mg levels increased, while TAS, albumin, and K levels decreased after 21 days. These increases/decreases in all serum biochemical parameters were generally higher in fish treated with Pb alone compared to fish treated with a mixture of Pb + NTA. This study shows that these changes in serum parameters could be used as an indicator to assess on metal toxicity.

The price of persistence: Assessing the drivers and health implications of metal levels in indicator carnivores inhabiting an agriculturally fragmented landscape

Patterns and practices of agricultural expansion threaten the persistence of global biodiversity. Wildlife species surviving large-scale land use changes can be exposed to a suite of contaminants that may deleteriously impact their health. There is a paucity of data concerning the ecotoxicological impacts associated with the global palm oil (Elaeis guineensis) industry. We sampled wild Malay civets (Viverra tangalunga) across a patchwork landscape degraded by oil palm agriculture in Sabah, Malaysian Borneo. Using a non-lethal methodology, we quantified the levels of 13 essential and non-essential metals within the hair of this adaptable small carnivore. We robustly assessed the biological and environmental drivers of intrapopulation variation in measured levels. Metal concentrations were associated with civet age, weight, proximity to a tributary, and access to oxbow lakes. In a targeted case study, the hair metal profiles of 16 GPS-collared male civets with differing space use patterns were contrasted. Civets that entered oil palm plantations expressed elevated aluminium, cadmium, and lead, and lower mercury hair concentrations compared to civets that remained exclusively within the forest. Finally, we paired hair metal concentrations with 34 blood-based health markers to evaluate the possible sub-lethal physiological effects associated with varied hair metal levels. Our multi-facetted approach establishes these adaptable carnivores as indicator species within an extensively altered ecosystem, and provides critical and timely evidence for future studies.

PLASMA BIOCHEMISTRY PROFILES OF WILD WESTERN TIGER SNAKES (NOTECHIS SCUTATUS OCCIDENTALIS) BEFORE AND AFTER SIX MONTHS OF CAPTIVITY

Urban wildlife often suffer poorer health than their counterparts living in more pristine environments due to exposure to anthropogenic stressors such as habitat degradation and environmental contamination. As a result, the health of urban versus nonurban snakes might be assessed by differences in their plasma biochemistries. We compared the plasma profiles of western tiger snakes (Notechis scutatus occidentalis) from a heavily urbanized wetland and a natural, nonurbanized wetland. Despite the urbanized snakes having lower body mass index, we found no significant difference between the plasma profiles of the two populations. We collected snakes from each population and kept them in captivity for 6 mo, providing them with stable conditions, uncontaminated (exempt from heavy metals and pesticides) food and water, and lowered parasite intensity in an attempt to promote better health through depuration. After captivity, snakes experienced a significant improvement in body mass index and significant changes in their plasma profiles. Snakes from the natural wetland initially had more variation of DNA damage; mean concentration of DNA damage in all snakes slightly decreased, but not significantly, after captivity. We present the plasma biochemistry profiles from western tiger snakes both before and after captivity and suggest a period of removal from natural stressors via captivity may offer a more reliable result of how plasma profiles of healthy animals might appear.

Associations of Particulate Matter Sizes and Chemical Constituents with Blood Lipids: A Panel Study in Guangzhou, China

Existing evidence is scarce concerning the various effects of different PM sizes and chemical constituents on blood lipids. A panel study that involved 88 healthy college students with five repeated measurements (440 blood samples in total) was performed. We measured mass concentrations of particulate matter with diameters ≤ 2.5 μm (PM_2.5), ≤1.0 μm (PM_1.0), and ≤0.5 μm (PM_0.5) as well as number concentrations of particulate matter with diameters ≤ 0.2 μm (PN_0.2) and ≤0.1 μm (PN_0.1). We applied linear mixed-effect models to assess the associations between short-term exposure to different PM size fractions and PM_2.5 constituents and seven lipid metrics. We found significant associations of greater concentrations of PM in different size fractions within 5 days before blood collection with lower high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A (ApoA1) levels, higher apolipoprotein B (ApoB) levels, and lower ApoA1/ApoB ratios. Among the PM_2.5 constituents, we observed that higher concentrations of tin and lead were significantly associated with decreased HDL-C levels, and higher concentrations of nickel were associated with higher HDL-C levels. Our results suggest that short-term exposure to PM in different sizes was deleteriously associated with blood lipids. Some constituents, especially metals, might be the major contributors to the detrimental effects.

Wild black rats (Rattus rattus Linnaeus, 1758) as zoomonitor of genotoxicity and systemic toxicity induced by hazardous emissions from Abule Egba unsanitary landfill, Lagos, Nigeria

Wild black rats (Rattus rattus) inhabiting Abule Egba landfill (AEL) were used as zoomonitor to assess health risk associated with exposure to hazardous chemicals from landfills. Twenty five R. rattus (16♂ and 9♀) captured within AEL and 15 (9♂ and 6♀) (control) caught from Iyano Ipaja (10 km away from AEL) were examined for bone marrow micronucleated polychromatic erythrocytes (MNPCE) and polychromatic erythrocytes/normochromatic erythrocytes (PCE/NCE) ratio, abnormal sperm morphology, alterations in hematological indices and erythrocyte morphology, and histopathology of the viscera using standard protocols. There was significant (p < 0.05) increase in MNPCE but decrease PCE/NCE ratio in bone marrow cells of exposed rats than the reference site. MNPCE was insignificantly higher in male than females. Cauda epididymal sperms from exposed rats showed significant high frequency of teratozoospermia. Erythrocyte count, hemoglobin concentrations, percentage hematocrits, mean corpuscular hemoglobin concentrations, leucocyte count, and lymphocytes decreased while mean corpuscular volume, neutrophils, and mean corpuscular hemoglobin increased in the exposed rats compared to the control. Also, abnormal erythrocyte morphology: acanthocytes, codocytes (target cells), schizocytes, and tear drops significantly increased in the exposed rats. Marginal sexual dimorphism was observed between males and females in the incidence of hematological indices. Histopathological lesions including interstitial edema, hemorrhage, lymphoid depletion, cellular infiltrations, proliferation of the alveolar pneumocytes, necrosis, tissue degeneration, and reduced germinal epithelium were observed in the testes, liver, lungs, heart, kidney, and spleen from the exposed rats compared to the control. Some physicochemicals and metals analyzed in leachates from the landfill are capable of inducing genome instability and systemic toxicity in the exposed rats. Rattus rattus exposed to hazardous chemicals from AEL harbored somatic and germ cell mutations, and tissue damage compared to the control rats. We suggest that R. rattus are useful sentinel for genotoxicity and system toxicity assessment of landfill-polluted sites.Graphical abstract.

Multiple metal exposure and platelet counts during pregnancy: A repeated measure study

BACKGROUND

Evidence from animal and in vitro studies suggest that some metals interfere with normal platelet counts (PLT). However, limited human studies have investigated the association of metals and PLT, a marker of hematologic and hemostatic, particularly in susceptible populations such as pregnant women.

OBJECTIVES

Our purpose was to investigate the associations of repeated measures of 13 urinary metals with PLT during pregnancy.

METHODS

The present study involved 3911 pregnant women participating in a prospective cohort study in Wuhan, China, from 2013 to 2016. We measured 13 metals in urine and PLT in blood samples collected in the first, second, and third trimester (median = 13, 24, and 35 weeks of gestation, respectively). Mixed linear models and general linear models were applied to analyze the associations between multiple metals and PLT during pregnancy. The odds ratio (OR) for gestational thrombocytopenia was examined using generalized estimating equations.

RESULTS

After adjusting for other metals and covariates, the repeated measure analyses showed that decreased levels of PLT were associated with a 10-fold increase in urinary concentration of cadmium (Cd) [percent difference (%Δ) = -5.02, 95%CI = -9.53, -0.29], manganese (Mn) [percent difference (%Δ) = -4.63, 95%CI = -7.50, -1.67], and arsenic (As) [percent difference (%Δ) = -4.56, 95%CI = -8.11, -0.86]. Cross-sectional analyses by trimesters revealed that Cd was inversely associated with PLT through the three trimesters. In addition, Cd was associated with an increased OR of 1.80 (95%CI: 1.26, 2.56), 1.65 (95%CI: 1.05, 2.59), 1.54 (95%CI: 1.02, 2.33) for gestational thrombocytopenia in the first, second, and third trimester, respectively.

CONCLUSIONS

Our study suggested an association of Cd, Mn, and As with decreased PLT during pregnancy. Particularly, Cd may increase the risk of gestational thrombocytopenia.

The remedial effect of Thymus vulgaris extract against lead toxicity-induced oxidative stress, hepatorenal damage, immunosuppression, and hematological disorders in rats

The Thymus vulgaris (T. vulgaris) has been used in foods for the flavor, aroma, and preservation and in folk medicines. The objective of the present work was to determine the antioxidant and protective effects of T. vulgaris extract against lead (Pb)-intoxicated rats. A thirty-two male Sprague-Dawley were randomly assigned into 4 equal groups and treated for six weeks as follows: group I (GP-I), served as negative control; GP-II, -III, and -IV received either Pb acetate in drinking water (500 mg/L), T. vulgaris extract (500 mg/kg/day) by oral gavage or Pb acetate with T. vulgaris extract, respectively. Blood samples were collected at the end of the study week 6 to measure the hepatic and renal biochemical markers, complete blood count alongside the serum levels of interleukin (IL)-1β, IL-6, IL-10, tumor necrosis (TNF)-α, and interferon (IFN)-γ. Additionally, liver and kidney tissue specimens were collected for histopathology as well as to measure the antioxidant-reduced glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), and superoxide dismutase (SOD) alongside the lipid peroxidation marker, malonaldehyde (MDA). The results indicated that Pb toxicity increased the serum levels of IL-1β, IL-6, and TNF-α, whereas IL-10 and IFN-γ were reduced. The results showed disturbed liver and renal functions; increased serum levels of ALT, AST, ALP, total bilirubin, creatinine, and urea; and decreased total protein, albumin, and calcium. The GSH, Gpx, and CAT levels were significantly decreased in the Pb-administrated group, while MDA was increased. However, regarding the hepatorenal markers, those animals treated with T. vulgaris alone did not induce any significant changes. Moreover, the combined treatment with T. vulgaris extract together with Pb showed significant improvement in Pb-induced toxicity in all the tested parameters compared to the negative control group. We investigated the potential protective effects of the medicinal plant T. vulgaris in vivo, since there are no publications that address the potential protective effect of this leaf extract against Pb-induced hepatorenal toxicity. Our studies concluded that the T. vulgaris extract reduces Pb overload in hepatorenal tissues, and that this has a potential immunomodulatory role, antioxidant activity, and a protective effect against Pb toxicity.

Ecotoxicological Effect of Single and Combined Exposure of Carbamazepine and Cadmium on Female Danio rerio: A Multibiomarker Study

In aquatic environments, organisms are exposed to mixtures of pollutants which may change the toxicity profile of each contaminant, compared to its toxicity alone. Carbamazepine (CBZ) and cadmium (Cd) are among the pollutants that co-occur in aquatic environments. To date, most research about their toxicity towards aquatic vertebrates is based on single exposure experiments. The present study aims to evaluate single and combined effects of CBZ and Cd on biomarkers in female Danio rerio (zebrafish) by exposing them to environmentally relevant concentrations of these two pollutants for ten days. Four kinds of biomarkers involved in antioxidant systems, energy metabolism, nervous system, and endocrine disruption, respectively, were studied. Our research results coincided with those of former studies in single exposure experiments. However, the combined exposure of CBZ and Cd exerted different responses from other studies in which these two contaminants were examined alone in zebrafish. The present study evidenced the need to conduct more coexposure studies to enhance the environmental relevance of these experimental results.

Is blood a reliable indicator of trace metal concentrations in organs of small mammals?

In wildlife ecotoxicology, the rationale for using blood rather than other body fluids or tissues is that sampling blood is a minimally invasive technique without animal mortality, providing both ethical and scientific benefits. To date, few studies are available on the relationships between blood and organ metal concentrations of small mammals living in contaminated sites. The present work aimed to study the relationships between the concentrations of 18 essential and nonessential metals in blood and their concentrations in the liver and kidneys, two accumulation and target organs, in wood mice from a former lead and zinc smelter, Metaleurop Nord, in northern France. The results from Se, Pb and Tl indicate that blood levels may be used to predict concentrations in organs of small mammals. Conversely, for Cd, Cu, Fe, Mo, Ti and Zn, blood concentrations were poorly or not related to liver and kidney concentrations. In addition to accurately predicting the concentrations of some metals in target organs, blood can provide important information about the physiological and biochemical status of organisms, but further toxicokinetic research is required to develop the use of blood sampling as a minimally invasive biomonitoring and ecotoxicological method in wildlife.

Stone quarrying induces organ dysfunction and oxidative stress in Meriones libycus

Exposure to heavy metal-containing dust arising from stone quarrying may cause severe health problems. The aim of this study was to evaluate the impact of stone quarrying in Riyadh (Saudi Arabia) on the Libyan jird Meriones libycus. Soil samples and jirds were collected from four sites located at different distances from the quarrying area. Soil from the first (500 m away from the quarry) and second (1800 m away) sites showed a significant increase in cadmium (Cd), lead (Pb), nickel (Ni), and vanadium (V) when compared with the reference site (38,000 m away). Jirds at these sites exhibited significant increases in liver, kidney, lung, and fur levels of Cd, Pb, Ni, and V. Serum transaminases, creatinine, and malondialdehyde (MDA) levels were significantly increased in jirds, whereas reduced glutathione (GSH) levels decreased. Liver, kidney, and lung tissues of jirds, collected from the first and second sites, showed significantly increased MDA and decreased GSH levels. Additionally, animals at both sites showed altered hematological parameters and several histopathological changes in their liver, kidney, and lung. Soil and animals at the third site (7300 m away) showed no significant changes. Thus, our study showed the impact and hazardous effects of quarrying on the liver, kidney, lung, and hemogram of M. libycus. These findings can provide scientific evaluation for studying the impact of quarrying on the workers and communities living close to the studied area.

Lead exposure is associated with risk of impaired coagulation in preschool children from an e-waste recycling area

Environmental lead exposure leads to various deleterious effects on multiple organs and systems, including the hematopoietic system. To explore the effects of lead exposure on platelet indices in preschool children from an informal, lead-contaminated electronic waste (e-waste) recycling area, we collected venous blood samples from 466 preschool children (331 from an e-waste area (Guiyu) and 135 from a non-e-waste area (Haojiang)). Child blood lead levels (BLLs) were determined by graphite furnace atomic absorption spectrophotometry, while platelet indices were quantified using a Sysmex XT-1800i hematology analyzer. Higher blood lead levels are observed in e-waste lead-exposed preschool children. Significant relationships between high blood lead levels (exceeding current health limits) and elevated platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV), and platelet large cell ratio (P-LCR) were also uncovered. Furthermore, the median PLT and PCT levels of children from the exposed group both exceeded the respective recommended maximum reference range value, whereas the reference group did not. Location of child residence in Guiyu and BLLs were both risk factors related to platelet indices. These results suggest that high blood lead exposure from e-waste recycling may increase the risk of an amplified coagulation process through the activation of platelets in preschool children.

PM2.5-bound metal metabolic distribution and coupled lipid abnormality at different developmental windows

Atmospheric fine particulate matter (PM_2.5) is a serious threat to human health. As a toxicant constituent, metal leads to significant health risks in a population, but exposure to PM_2.5-bound metals and their biological impacts are not fully understood. In this study, we determined the metal contents of PM_2.5 samples collected from a typical coal-burning city and then investigated the metabolic distributions of six metals (Zn, Pb, Mn, As, Cu, and Cd) following PM_2.5 inhalation in mice in different developmental windows. The results indicate that fine particles were mainly deposited in the lung, but PM_2.5-bound metals could reach and gather in secondary off-target tissues (the lung, liver, heart and brain) with a developmental window-dependent property. Furthermore, elevations in triglycerides and cholesterol levels in sensitive developmental windows (the young and elderly stages) occurred, and significant associations between metals (Pb, Mn, As and Cd) and cholesterol in the heart, brain, liver and lung were observed. These findings suggest that PM_2.5 inhalation caused selective metal metabolic distribution in tissues with a developmental window-dependent property and that the effects were associated with lipid alterations. This provides a foundation for the underlying systemic toxicity following PM_2.5 exposure based on metal components.

Endoplasmic Reticulum Stress and Apoptosis Triggered by Sub-Chronic Lead Exposure in Mice Spleen: a Histopathological Study

Lead (Pb) is an environmental oncogenic metal that induces immunotoxicity and anaemia. Emerging evidence has linked Pb toxicity with endoplasmic reticulum-driven apoptosis and autophagy. Glucose-regulated protein of 78 kDa (Grp78 or binding immunoglobulin protein (BiP)), a master endoplasmic reticulum chaperone, drives macrophage activation and regulates protein folding and calcium flux in response to heavy metals. The spleen may be involved in Pb poisoning due to its crucial role in erythrocatheresis and immune response, although there are no data to support this theory. Here, we found haematic and histopathological changes in the spleen of mice exposed to medium doses of Pb acetate (200 ppm-1 mM) in drinking water for 45 days. Pb deposition was also detected in organs such as the liver, kidney, brain, bone, blood and faeces, indicating an accumulation of this metal despite relatively short exposure time. Blood Pb content (BBL) reached 21.6 μg/dL; echinocytes and poikilocytes were found in Pb smears of treated group. Inside the spleen, higher Fe(II) and Fe(III) deposits inside macrophages were observed. Grp78 immunostaining, weakly expressed in spleen cells of control mice, after Pb exposure was specifically restricted to macrophages and megakaryocytes of the marginal zone of red pulp. Furthermore, Pb exposure induced superoxide dismutase 1 (SOD1) expression, cleaved caspase-3 and p62/SQSTM1, consistent with oxidative stress, apoptosis and dysregulated autophagy in spleen compartments. We suggest that even at a middle dose, oral Pb intake induces oxidant iron deposition in the spleen and that this may trigger sustained Grp78 redistribution to cells, thus leading to oxidative and autophagy dysfunction as early local reactions to this dangerous metal.

Curcumin Ameliorates Lead (Pb(2+))-Induced Hemato-Biochemical Alterations and Renal Oxidative Damage in a Rat Model

This study aims to evaluate the protective role of curcumin (Curc) against hematological and biochemical changes, as well as renal pathologies induced by lead acetate [Pb (CH3COO)2·3H2O] treatment. Male albino rats were intraperitoneally treated with Pb(2+) (25 mg of lead acetate/kg b.w., once a day) alone or in combination with Curc (30 mg of Curc/kg b.w., twice a day) for 7 days. Exposure of rats to Pb(2+) caused significant decreases in hemoglobin (Hb) content, hematocrit (Ht) value, and platelet (Plt) count, while Pb(2+)-related leukocytosis was accompanied by absolute neutrophilia, monocytosis, lymphopenia, and eosinopenia. A significant rise in lipid peroxidation (LPO) and a marked drop of total antioxidant capacity (TAC) were evident in the kidney, liver, and serum of Pb(2+) group compared to that of control. Furthermore, significantly high levels of total cholesterol (TC), triglycerides (TGs), and low-density lipoprotein cholesterol (LDL-C), and a sharp drop in serum high-density lipoprotein (HDL-C) level were also seen in blood after injection of Pb(2+). Additionally, hepatorenal function tests were enhanced. Meanwhile, Pb(2+) produced marked histo-cytological alterations in the renal cortex. Co-administration of Curc to the Pb(2+)-treated animals restored most of the parameters mentioned above to near-normal levels/features. In conclusion, Curc appeared to be a promising agent for protection against Pb(2+)-induced toxicity.

Blood parameters as biomarkers of cadmium and lead exposure and effects in wild wood mice (Apodemus sylvaticus) living along a pollution gradient

Small mammal populations living on contaminated sites are exposed to various chemicals. Lead (Pb) and cadmium (Cd), two well-known nonessential trace metals, accumulate in different organs and are known to cause multiple adverse effects. To develop nonlethal markers in ecotoxicology, the present work aimed to study the relationships between blood parameters (hematocrit, leukocyte levels and granulated erythrocyte levels) and Cd and Pb concentrations in the soil and in the liver and kidneys of wood mice (Apodemus sylvaticus). Individuals were trapped along a pollution gradient with high levels of Cd, Pb and zinc (Zn) contamination. The results indicated that hematological parameters were independent of individual characteristics (age and gender). Blood parameters varied along the pollution gradient, following a pattern similar to the accumulation of Cd in the organs of the wood mice. No relationship was found between the blood parameters studied and Pb concentrations in the organs or in the environment. The hematocrit and leukocyte number decreased with increasing concentrations of Cd in the kidneys and/or in the liver. Moreover, the hematocrit was lower in the animals that were above the thresholds (LOAELs) for Cd concentrations in the liver. These responses were interpreted as a warning of potential negative effects of Cd exposure on the oxygen transport capacity of the blood (e.g., anemia). The present results suggest that blood parameters, notably hematocrit, may offer a minimally invasive biomarker for the evaluation of Cd exposure in further ecotoxicological studies.