Pb-treated Group Research Articles

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.

Sublethal Concentrations of Cadmium and Lead: Effects on Hemato-Biochemical Parameters and Tissue Accumulation in Wallagu attu.

The exposure of fish to heavy metals can significantly impact physiological processes and potentially lead to adverse health effects. This study assesses the effects of exposure to Cd and Pb sublethal concentrations in water on Wallagu attu. A total of 48 fish with an average body weight of 145.5 ± 26g were distributed among three groups (control, Cd-treated, and Pb-treated) within 60L fiberglass tanks. They were exposed to30% sublethal concentrations of Cd and Pb for durations of 1, 15, and 30 days. Following this exposure, an assessment was conducted on metal bioaccumulation and hemato-biochemical responses. Results revealed a significantly (P < 0.05) higher concentration of heavy metals in the fish tissues of metals exposed groups than in the control. The concentration of Cd and Pb increases in fish tissues (kidney > gills > intestine) with exposure time. In most cases, the Pb-exposed group exhibited significantly (P < 0.05) higher concentrations of Pb in different tissues than the Cd-treated group. With extended exposure time, the activities of CAT and SOD show a significant decrease in both Cd and Pb-treated groups. However, the reduction in activities was more pronounced in the Cd-exposed group. On 15 and 30 days, the levels of red blood cells (RBC), hemoglobin (HB), hematocrit (HCT), and total protein (TP) decrease in groups exposed to Cd and Pb. The cortisol and glucose levels exhibit a more noticeable (P < 0.05) increase with prolonged exposure to Cd and Pb than the control group. On day 30, the survival rate decreased more in the Pb-exposed group. The findings of this study indicate that exposure to sublethal doses of Cd and Pb induces stress in Wallagu attu, resulting in rapid changes in specific hemato-biochemical parameters.

Spirulina supplementation to alleviate negative effects of lead in layer chicken.

Lead (Pb), a toxic heavy metal, is a serious concern for poultry that negatively affects their productivity and health. To combat those issues efficiently, it is necessary to include feed supplements that have rich antioxidant properties for satisfactory health and productivity. Spirulina platensis (Sp), a microalgae, is a compound that provides several health benefits for humans and animals. This study explores that supplementation of Sp in diet as well as in water reduces the burden of Pb in different tissues, improves hematology, and improves the productive performance of advanced-age laying hens. Forty birds were separated into four groups: the control (C), Spirulina (Sp), Pb, and (Pb + Sp) groups. The Pb group was given Pb acetate at a dose of 2 gm/l in water ad libitum for 4 weeks. Sp group was fed Sp at a dose of 4 gm/kg feed. The Pb + Sp group was given Pb and Sp as in the previous groups. Productive performance and hematology such as hemoglobin (Hb), packed cell volume, red blood cell, mean corpuscular volume, mean corpuscular Hb (MCH) concentration, and MCH were significantly (p < 0.05) decreased in Pb-treated groups compared to controls. The distribution of Pb concentration was highest in the bones and lowest in the gizzard. However, Sp treatment significantly (p < 0.05) increased the productive performance and the hematological parameters. Moreover, Pb concentration in different organs significantly decreased in the group treated with Sp. This study indicates that Sp can possibly be used as a natural and powerful dietary additive to mitigate heavy metal intoxication in chickens, thereby being efficient and effective for production.

Lead exposure disrupted ileal barrier of developmental Japanese quails(Coturnix japonica): Histopathological damages, microbiota dysbiosis and immune disorder

The gut barrier plays an essential role in maintaining homeostasis and is usually composed of a mechanical barrier, a chemical barrier, an immune barrier, and a biological barrier. However, the impacts of lead (Pb) exposure on avian gut barrier are still unclear. Therefore, the present study tried to determine the toxic effects of Pb on ileal barrier of a biological model-Japanese quail (Coturnix japonica). One-week old quails were exposed to 0, 50, 500 and 1000 ppm Pb in drinking water for 5 weeks. The results showed mechanic barrier in the ileum was disrupted with microstructural deformation featured by epithelial cell abscission, villi contractions and goblet cells reduction as well as ultrastructural changes characterized by swollen mitochondria, blurry tight junctions and microvilli subtraction. Meanwhile, the expression of genes associated with intestinal tight junctions was downregulated in Pb-treated groups indicating tight junction malfunction. Moreover, less mucus and downregulation of expression of mucin2 (Muc2) and Krüppel-like factor 4 (Klf4) indicated chemical barrier disturbance by Pb. In addition, the alteration of microbial diversity and emergence of pathogen bacteria suggested ileal biological barrier disruption by Pb. Furthermore, Pb caused immune dysfunction in the ileum through promoting the expression of pro-inflammatory factors including interleukin 1 beta (IL-1β), interleukin 6 (IL-6), Interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α) and nuclear factor kappa B (NF-κB) and inhibiting the expression of anti-inflammatory factor interleukin 10 (IL-10). The present study demonstrated that Pb may pose health risks to birds through gut barrier damages.

Reproductive toxicity induced by lead exposure: Effects on gametogenesis and sex steroid signaling in teleost fish

Lead (Pb) is an emerging contaminant widely distributed in aquatic environments, which has serious effects on human and animal health. In this study, we determined whether Pb exposure affects gametogenesis, sex steroids, estrogen (ERα and ERβ), and androgen (AR) receptors. Adult specimens of Astyanax bimaculatus were exposed in duplicate to 15, 50, and 100 μg/L of lead acetate, whereas the control group was not exposed. After 28 days of exposure, fish were euthanized and samples of the gonads, liver, and blood were collected for analysis. The results indicated a reduction in the gonadosomatic index as well as the diameters of the vitellogenic follicles and seminiferous tubules in the exposed groups. Morphometry of gametogenesis revealed inhibition of the secondary oocyte growth and a reduction in the number of spermatozoa in the 50 and 100 μg/L Pb-treated groups. In females, plasma 17β-estradiol (E2) increased following 15 and 50 μg/L Pb treatment, whereas males exhibited an increase in E2 and 11-ketotestosterone following treatment with 15 and 100 μg/L Pb, respectively. Vitellogenin was significantly reduced in females exposed to 100 μg/L Pb, but metallothionein levels were unchanged. ERα, ERβ, and AR were immunolocalized in the somatic and germ cells, with increased ovarian expression of ERα and Erβ in the 100 μg/L Pb-treated group, but no significant difference in AR among the groups. In males, only ERα increased in the 100 μg/L Pb-treated group. These results indicate that Pb exposure impairs gametogenesis, disrupts estrogen receptor signaling, and affects the expression of major reproductive biomarkers in A. bimaculatus.

Glycine protects the male reproductive system against lead toxicity via alleviating oxidative stress, preventing sperm mitochondrial impairment, improving kinematics of sperm, and blunting the downregulation of enzymes involved in the steroidogenesis

Lead (Pb) is a highly toxic heavy metal widely dispersed in the environment because of human industrial activities. Many studies revealed that Pb could adversely affect several organs, including the male reproductive system. Pb-induced reproductive toxicity could lead to infertility. Thus, finding safe and clinically applicable protective agents against this complication is important. It has been found that oxidative stress plays a fundamental role in the pathogenesis of Pb-induced reprotoxicity. Glycine is the simplest amino acid with a wide range of pharmacological activities. It has been found that glycine could attenuate oxidative stress and mitochondrial impairment in various experimental models. The current study was designed to evaluate the role of glycine in Pb-induced reproductive toxicity in male mice. Male BALB/c mice received Pb (20 mg/kg/day; gavage; 35 consecutive days) and treated with glycine (250 and 500 mg/kg/day; gavage; 35 consecutive days). Then, reproductive system weight indices, biomarkers of oxidative stress in the testis and isolated sperm, sperm kinetic, sperm mitochondrial indices, and testis histopathological alterations were monitored. A significant change in testis, epididymis, and Vas deferens weight was evident in Pb-treated animals. Markers of oxidative stress were also significantly increased in the testis and isolated sperm of the Pb-treated group. A significant disruption in sperm kinetic was also evident when mice received Pb. Moreover, Pb exposure caused significant deterioration in sperm mitochondrial indices. Tubular injury, tubular desquamation, and decreased spermatogenic index were histopathological alterations detected in Pb-treated mice. It was found that glycine significantly blunted oxidative stress markers in testis and sperm, improved sperm mitochondrial parameters, causing considerable higher velocity-related indices (VSL, VCL, and VAP) and percentages of progressively motile sperm, and decreased testis histopathological changes in Pb-exposed animals. These data suggest glycine as a potential protective agent against Pb-induced reproductive toxicity. The effects of glycine on oxidative stress markers and mitochondrial function play a key role in its protective mechanism.

Effect of Phenobarbital on Elevated Direct Bilirubin Concentrations in Neonates and Infants in the Neonatal Intensive Care Unit

OBJECTIVE Few studies have evaluated the effect of phenobarbital (PB) on elevated direct bilirubin (DB) plasma concentrations in neonates and infants, and none have compared its effect with a control group with matched study baseline DB values. The purpose of this study was to quantify changes in elevated DB plasma concentrations (≥2 mg/dL) in neonates and infants between a PB-treated and control group. METHODS A retrospective, observational, matched, cohort study was performed comparing patients between a PB-treated group and a control group with similar study baseline plasma DB values ≥2 mg/dL over an 8-week period. The percent change in DB plasma concentrations from study baseline was compared for each week of the study period. RESULTS During the 8-year study period, 310 patients had DB plasma concentrations ≥2 mg/dL, of which 26 remained in each group after exclusions. The PB group had increased DB concentrations and the control group had decreased DB concentrations when compared with their study baseline DB concentrations each week of the study period. By study end, the mean DB concentration increased by 11.2% in the PB group and decreased by 48.5% in the control group (p = 0.02). In multiple regression analysis, only birth weight (standardized coefficient = 0.44, p = 0.02), and gastrointestinal obstruction (standardized coefficient = −0.4, p = 0.03) were associated with significant percent change in DB concentrations. CONCLUSIONS This study demonstrated PB does not improve cholestasis in neonates and infants.

Evaluation of lead toxicity on the retina of pregnant rats and their pups: the possible ameliorative role of pomegranate juice

Background: Lead (Pb) exposure even at a low dose can induce functional and structural impairments in both humans and experimental animals. The present study evaluated the potential ameliorative role of pomegranate juice (PJ), as a powerful antioxidant fruit against histopathological and ultrastructural changes caused by Pb in the retina of pregnant rats and their neonates. Methods: 24 pregnant female rats were selected and randomly divided into four groups (n=6): control, PJ supplemented (100 μL PJ), Pb treated (18.5 mg / kg B.Wt), and Pb co-supplemented alternatively with PJ group. After birth, the mother rats, as well as their neonates at different ages (7, 14, and 21 days old), were dissected and the eyes were removed for histological, ultrastructural, and immunohistochemical investigation of the retina. Results: The obtained results revealed deleterious histological and ultrastructural lesions in all retinal cell layers of Pb-treated female rats and their offspring. Such lesions included hypertrophied cells of retinal pigmented epithelium (RPE) with pronounced vacuolated mitochondria and fragmented Bruch's membrane. The outer and inner segments of photoreceptors appeared fragmented and detached from the RPE. Additionally, the outer nuclear layer (ONL) and inner nuclear layer (INL) appeared disorganized with vacuolated cytoplasm and pyknotic nuclei. The immunohistochemical results displayed glial fibrillary acidic protein (GFAP) weak expression and P53 strong expression in the retinal sections of the Pb-treated group of female rats and their neonates if compared with control. Conclusions: PJ successfully alleviated the deleterious histological and ultrastructural as well as immunohistochemical changes induced by lead.

Relationships between lead-induced learning and memory impairments and gut microbiota disturbance in mice

Objective: To explore the effect of lead exposure on the neurobehavior and gut microbiota community structure in mice. Methods: In August 2019, 64 C57BL/6 mice were randomly divided into 4 groups: control group (0 ppm) , low lead exposure group (20 mg/l) , medium lead exposure group (100 mg/l) and high lead exposure group (500 mg/l) . During the experiment, they were free to eat and drink. The drinking water of the lead exposure group was mixed with lead acetate, and sodium acetate was added in the control group. After 10 weeks of exposure, the Morris water maze was used to test the learning and memory ability of each group of mice, and then they were sacrificed for sampling. ICP-MS was used to detect lead content in whole blood and brain tissue. ELISA was used to determine the level of IL-1β in mouse serum. 16S rRNA sequencing was used to detect the structural diversity of the intestinal flora in feces, and then the correlation between the flora and behavior indicators was analyzed. Results: In the Morris water maze experiment, compared with the control group, there was no significant difference in the body weight and swimming speed of the mice in the lead exposure groups. The escape latency of the mice in the 100 mg/l and 500 mg/l dose groups was prolonged, and the number of platform crossings decreased (P<0.05) ; meanwhile, the staying time of the mice in the 500 mg/l Pb-treated group in the target quadrant was lower than that of the control group, and the difference was statistically significant (P<0.05) . Compared with the control group, the blood lead content of the mice in each lead exposure group was significantly increased, and the brain lead content of mice in the 500 mg/l dose group was significantly elevated (P<0.05) . The serum IL-1β levels of mice in each lead exposure group were higher than those of the control group (P<0.05) . At the phylum level, the relative abundance of the Proteobacteria phylum in all of Pb-treated groups was significantly increased (P<0.05) ; at the genus level, Allobaculum, Desulfovibrio, Lachnospiraceae_NK4A136_group, Turicibacter and Ureaplasma were significantly increased (P<0.05) . Among them. The relative abundance of Desuffaoibrio, Turici bacter, and Ureaplasma was negatively correlated with the residence time of mice in the quadrant of the platform (r=-0.32, -0.29, -0.44, P<0.05) . Conclusion: Lead exposure induced learning and memory impairments in mice, which may be related to the disturbance of the gut microbiota.

Effect of l-carnitine supplementation on lead acetate-induced liver cell apoptosis and inflammation: role of caspase-3 and glycogen synthase kinase-3β enzymes

AimThe study aimed at studying the hepatoprotective effect of l-carnitine against lead (Pb) acetate-induced hepatocellular injury, emphasizing the role of caspase-3 and glycogen synthase kinase-3β in hepatocellular apoptosis and inflammation. Materials and methodsMale Wistar rats were used. The experimental approach involved estimation of the liver enzymes' serum levels. Oxidative and inflammatory biomarkers were measured in hepatic tissue homogenates. Paraffin-embedded hepatic sections were prepared for histopathology and immunohistochemistry. Quantitative determination of the phosphorylated glycogen synthase kinase-3 beta was performed. Key findingsThe serum showed a significant elevation in ALT, AST, and LDH; tissue homogenates showed significant elevation in lipid peroxide and inflammatory biomarkers with significant reduction in reduced glutathione in the Pb acetate-treated group. Co-administration of l-carnitine with Pb acetate produced significant reduction in liver enzymes with significant improvement in oxidant, antioxidant and inflammatory markers. Lead acetate treatment significantly reduced the phosphorylated glycogen synthase kinase-3 beta, while l-carnitine enhanced its phosphorylation. Histopathological examination showed inflammatory reaction around blood vessels with fatty degeneration in hepatocytes of the Pb acetate intoxicated group. l-Carnitine caused a decrease in hepatic damage with minimal vascular alterations in central vein. Caspase-3 expression in hepatocytes was decreased in Pb-treated group supplemented with l-carnitine. SignificanceOur study reveals that oxidative stress and inflammation participate in Pb acetate-induced hepatocellular injury. Glycogen synthase kinase-3β and caspase-3 play role in Pb acetate-induced hepatic damage. l-Carnitine shows significant protective effects against hepatocellular apoptosis and inflammation induced by Pb acetate through antioxidant, anti-inflammatory and anti-apoptotic pathways in part mediated by GSK-3β inhibition.

Assessment of Role and Efficacy of Curcumin and Quercetin in Preventing Lead-Induced Oxidative Stress in Rats.

Lead (Pb) is found in almost all phases in environment and biological systems. Pb stimulated oxidative stress is a state that involves the generation of free radicals beyond the permissible limits, which can deplete the antioxidant reserves and can result in oxidative stress, thus hampering the ability of the biological system to reverse the result. Exposure of rats to Pb (25mg/kg body weight) for 8weeks caused an increase in Pb levels in blood and brain. Activity of delta-aminolevulinic acid dehydratase (δ-ALAD) and antioxidant enzymes such as Superoxide dismutase (SOD) and Catalase (CAT) decreased in the blood of Pb-treated group with a concomitant increase in the level of lipid peroxidation (LPO) and no significant change in the level of reduced glutathione (GSH) level was found. Interestingly, co-treatment of Pb-treated rats with curcumin (30mg/kg body weight) and quercetin (30mg/kg body weight) for 8weeks caused a significant decrease in Pb levels of blood and all brain regions versus those treated with Pb alone. A significant improvement in levels of MDA, δ-ALAD, SOD and CAT activities was observed in rats simultaneously treated with curcumin or Quercetin or both with lead. Therefore, the ameliorative impact of curcumin and Quercetin might be due to their antioxidant property hence were able to counter the oxidative stress generated by Pb. These results suggest that combination of curcumin and Quercetin could be utilized as a possible supplement with the relevant therapeutics in the suitable management of Pb toxicity.

Protective Effect of Quercetin on Testis Structure and Apoptosis Against Lead Acetate Toxicity: an Stereological Study.

Exposure to environmental pollutants tightly impacts on the male fertility. In the present study, we examined the toxic effects of lead acetate (Pb) on testicular structure and the possible effect of quercetin on mitigating these effects. The apoptotic changes in the testes were also studied by the TUNEL assay and changes in apoptosis-related gene (Bax, Bcl-2, and caspase-3) expression. Twenty-one male mice were randomly divided into 3 groups of control, Pb, and lead acetate + quercetin. Testicular weight, both absolute and relative, was higher in Pb-exposed mice in comparison with the control and Pb-quercetin groups. The increase in size of testis was related to the lumen and connective tissue in this group. Lead acetate induced different patterns in testicular cell number; as spermatogonia, spermatocyte, and Sertoli cells number did not affect in lead acetate exposed group, while total number of round spermatids and long spermatids significantly reduced.In addition, Bcl-2 expression was downregulated, and Bax expression was upregulated in Pb-treated group in comparison with the control and Pb + quercetin groups. The TUNEL assay revealed that the number of apoptotic cells in Pb-treated group were increaed significantley in comparison to other groups. In conclusion, Pb administration adversely impacted on the cellular organization and activation of the apoptotic pathways in the testis; on the other hand, quercetin co-administration with lead partially ameliorated these adverse effects.

Metformin attenuates lead‐induced inflammatory and apoptotic lung injury through modulation of P53 and TNF‐α pathways in rats

Exposure to heavy metals, such as Lead (Pb) is a matter of growing concern and potential risk factor for developing inflammatory lung diseases. The aim of this study was to a) investigate the protective effect of metformin against Pb‐induced lung injury in rat and b) investigate the underlying mechanisms specifically the role of oxidative stress, inflammation and apoptosis. For this purpose, twenty‐four adult male Wistar albino rats weighing about 230 gm were randomly distributed into six study groups of four rats each. The first group received normal saline (0.5 ml/kg/day) for 6 consecutive days and served as a a Control. The second group received metformin (500 mg/kg) for 6 consecutive days. The third and fourth groups received a single dose of normal saline (0.5 ml/kg/day) for 3 consecutive days followed by lead nitrate (Pb) (25 and 50 mg/kg, i.p.) for 3 consecutive days, respectively. The fifth and sixth groups received metformin (500 mg/kg) for 3 consecutive days followed by Pb 25 and 50 mg/kg, i.p. plus metformin 500 mg/kg for additional 3 consecutive days, respectively. One day after the last dose, animals were a and blood samples were collected via cardiac puncture for determination the levels of Pb. Rats lung tissues were excised and processed for histopathological examination, determination the levels of mRNA and protein expression of target genes, Analysis of apoptosis and TNF‐α production were determined by flow cytometer. Our results showed that exposure to Pb caused induction of inflammatory cells infiltration, cell apoptosis, modulation of genes involving in inflammation and oxidation, induction of p53 and TNF‐α were demonstrated in Pb‐induced lung injury. Administration of metformin 500 mg/kg for 6 days resulted in a protective effect on the Pb‐induced inflammatory lung injury through induction of the expression levels of NQO1, SOD, HO‐1, and p53 genes. In addition, metformin treatment significantly reduced the production of TNF‐α and expression of IL‐6 while induced the expression of IL‐10 in Pb‐treated groups. In conclusion, these observations suggest that metformin processes anti‐inflammatory, antiapoptotic and the induction of antioxidants properties against Pb‐induced lung injuries.

Evaluating the role of vitexin on hematologic and oxidative stress markers in lead-induced toxicity in mice

We aimed to evaluate the effect of vitexin on some hematologic parameters and oxidative stress markers in lead-induced toxicity in mice. Forty adult male albino mice were divided into five groups of eight animals comprising: control; Pb; vitexin; Pb + vitexin; and Pb + vitexin (post) groups. Blood samples collected were analyzed using an auto hematology analyzer for sixteen parameters including red cell distribution width (RDW), red blood cell (RBC), and white blood cell (WBC). The levels of oxidative stress markers were also assessed. In Pb-treated group, RDW, RBC, MCV, Hb, Hct, granulocytes, and blood lead level were significantly different from the control group as well as Pb + vitexin (post) group. In Pb + vitexin groups, MCHC, platelets, and lymphocytes counts were significantly different from the control group. There was no difference in MPV, MID, and WBC between the groups. MDA level in Pb-treated group was significantly high while SOD and GPx levels were low. In Pb + vitexin-treated groups, SOD and GPx levels were significantly high while MDA was low. Pb-induced toxicity caused significant changes in the values of hematologic parameters and oxidative markers measured but vitexin was able to mitigate some of the changes. Some of the values were inconsistent with Pb intoxication.

Effect of Cadmium and Lead on Total Hemocyte Count of Achroia grisella Fabr. (Lepidoptera: Pyralidae)

The effect of cadmium (Cd) and lead (Pb) on total hemocyte count (THC) of Achroia grisella was examined under laboratory conditions. Larvae were reared on an artificial diet medium contaminated with three different concentrations (50, 100 and 200 mg/kg) of Cd and Pb. In the control group the insects fed a heavy metal free diet. All of the insects were kept at 25 ± 2 °C temperature, 60 ± 5% relative humidity and 16L:8D photoperiod conditions.The obtained data showed that the total hemocyte count of larvae exposed to Cd resulted in a significant decrease at all concentrations, whereas total hemocyte count of Pb-treated groups decreased only at the highest concentrations of Pb.

Lead-mediated inhibition of lysine acetylation and succinylation causes reproductive injury of the mouse testis during development

Lead (Pb), a widespread heavy metal, may induce serious diseases, particularly male reproductive injury. However, the mechanisms by which Pb induces testicular injury remain unclear. In this paper, we established a mouse model of Pb-induced testicular injury via an intraperitoneal injection of lead chloride at a concentration of 1.5 mg/kg body weight. We confirmed that Pb could induce a series of injuries, including a low litter size, smaller testes, more weak offspring, direct injury, and aberrant spermiogenesis. Our study demonstrated that Pb could inhibit lysine acetylation (Kac) and succinylation (Ksuc) via western blot (WB) and immunofluorescence (IF) analyses. We subsequently separated different germ cells that contained Pre-meiotic spermatogonia (SPG), meiotic spermatocyte (SPC), and round spermatid (RS) into the Pb-treated and control groups and verified that Pb inhibited Kac in SPC, RS, and particularly, during meiosis. Furthermore, our results regarding the inhibition of pyruvate kinase and mitochondrial electron transport chain complex I and II in the Pb-treated groups suggested that Pb may restrain key enzymes to block the TCA cycle and that the low TCA cycle activity could reduce the contents of two important metabolites, acetyl-CoA and succinyl-CoA, to inhibit Kac and Ksuc. Moreover, we examined the influences of the inhibition of Kac and Ksuc on spermiogenesis, which indicated that decreased Kac and Ksuc could impede the replacement of transition proteins in elongating sperm and disorder the distribution of germ cells in the seminiferous tubule. Our research provides novel insights into the mechanisms of Pb reproductive toxicity with respect to lysine acetylation and succinylation.

Thymoquinone ameliorates oxidative damage and histopathological changes of developing brain neurotoxicity

ABSTRACTLead (Pb) toxicity is known to be a chief environmental health issue, especially for pregnant women and young children. Today, the use of medicinal herbs in the treatment of many diseases and different toxic agents has become highly accepted due to their effectiveness and lower costs. Thymoquinone (TQ), which is extracted from Nigella sativa seeds, is a potent antioxidant and anti-inflammatory agent. This study was designed to explore the optional protectivity of TQ against maternal and fetal oxidative stress and brain damage induced by Pb administration. Pregnant rats were distributed into seven groups: control group, TQ group, DMSO group, two groups Pb-treated (160 and 320 ppm), and two groups Pb-treated (160 and 320 ppm) co-treated with TQ. Administration started from gestation day 1 (GD1) to day 20 (GD20) through oral gavage once daily. Lead administration caused a dose-dependent toxicity for both mothers and fetuses. Also, the histopathological assessment of the brains from Pb-treated groups showed marked alterations. Co-treatment of with TQ and Pb caused a significant decrease in Pb levels as compared with those treated with Pb alone and amelioration of histopathological changes in the brains. It was concluded that co-treatment of TQ along with gestational Pb exposure could mitigate the effects against Pb-induced maternal and fetal neurotoxicity.

Single and joint oxidative stress–related toxicity of sediment-associated cadmium and lead on Bellamya aeruginosa

The biotoxicity of heavy metals in sediments toward benthic organisms has evoked great concern for the health of freshwater ecosystems. This study applied a sediment toxicity testing protocol to investigate the single and joint toxicity of cadmium (Cd) and lead (Pb) on Bellamya aeruginosa. B. aeruginosa were exposed to different concentrations of Cd (5, 25, and 100 mg/kg), Pb (20, 100, and 400 mg/kg), and their different concentration combinations. A suite of biomarkers, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), metallothionein (MT), malondialdehyde (MDA), and acetylcholinesterase (AChE), were measured after 7, 14, 21, and 28 days of exposure to evaluate their oxidative stress status. Cell apoptosis of soft tissue was also determined after exposure. Results revealed that these endpoints represented sensitive biomarkers for the characterization of the oxidative stress response induced by these metals. Specifically, a decrease of SOD and GPx and an increase of MDA were indicative of the potential failure of the antioxidant defense system in neutralizing the reactive oxygen species (ROS) generated in the exposure of the Pb-treated group. The integrated biomarker response (IBR) index revealed the most significant sub-lethal toxicity for Pb-spiked sediments, leading to the highest rate of cell apoptosis (70.8%). Exposure to Cd resulted in a time- and dose-dependent effect on MT levels, which suggested active detoxification of this metal. Exposure to the mixture resulted in amelioration of Pb toxicity, likely due to the competitive binding of Cd to active enzyme, with the result of an observed antagonistic interaction. This study indicated that B. aeruginosa represents a good biomonitor for assessing Cd and Pb contamination of sediments, and laid the foundation for their potential risk assessments in freshwater ecosystems.

Urine NMR Metabolomic Study on Biochemical Activities to Investigate the Effect of P. betle Extract on Obese Rats.

The present studies are to evaluate the ability of PB to induce weight loss and urine metabolite profile of Piper betle L. (PB) leaf extracts using metabolomics approach. Dried PB leaves were extracted with ethanol 70% and the studies were performed in different groups of rats fed with high fat (HFD) and normal diet (ND). Then, fed with the PB extract with 100, 300, and 500mg/kg and two negative control groups given water (WTR). The body weights were monitored and evaluated. Urine was collected and 1H NMR-based metabolomics approach was used to detect the metabolite changes. Results showed that PB-treated group demonstrated inhibition of body weight gain. The trajectory of urine metabolites showed that PB-treated group gave the different distribution from week 12 to 16 compared with the control groups. In 1H NMR metabolomic approach analysis, the urine metabolites gave the best separation in principle component 1 and 3, with 40.0% and 9.56% of the total variation. Shared and unique structures (SUS) plot model showed that higher concentration PB-treated group was characterized by high level of indole-3-acetate, aspartate, methanol, histidine, and creatine, thus caused an increased the metabolic function and maintaining the body weight of the animals treated.

Neurodegeneration, demyelination, and astrogliosis in rat spinal cord by chronic lead treatment.

Early exposure to lead (Pb) has been associated with an elevated risk of developing neurodegenerative diseases. There is evidence that neuronal damage in chronic Pb exposure can be caused by the convergence of glial damage. Apoptosis may be a possible mechanism of Pb-induced cell death in the central nervous system. We tested cellular damage and apoptosis in the spinal cord of Wistar rats treated with Pb. Twelve rats were divided into two groups (n = 6): the control group was treated with only drinking water and the other group received 500 ppm of Pb acetate. After 3 months of Pb treatment, all animals were euthanized and spinal cords were extracted. Morphology was evaluated by Nissl and Kluver-Barrera stainings. Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Specific antibodies were used to evaluate Pb damage in oligodendrocytes, astrocytes, and microglia. A large number of apoptotic bodies was observed in the white matter of the Pb-treated group. The Pb-treated group also showed a reduced number of neurons and oligodendrocytes but had an increased number of astrocytes compared with the nontreated group. Our results demonstrate that chronic Pb treatment induces neurodegeneration, demyelination, and astrogliosis in the rat spinal cord.