Toxic effects of lead exposure in Wistar rats: involvement of oxidative stress and the beneficial role of edible jute (Corchorus olitorius) leaves

Snow White's tale in nephrology: the emerging threat of skin-whitening creams on kidney health

The timeless tale of Snow White, with its emphasis on fair skin as a beauty ideal, mirrors a contemporary issue in nephrology: the harmful impact of skin-whitening creams on kidney health. Fairness creams have deeply embedded themselves in global society, driven by a pervasive obsession with lighter skin tones as a symbol of beauty. This widespread use reflects deeply rooted cultural beliefs and social norms, despite the significant health risks associated with these products. Despite regulatory bans, these creams often contain hazardous substances such as hydroquinone, mercury, and arsenic, posing serious health risks. Mercury, a frequent component of these cosmetics, disrupts melanin synthesis by inhibiting tyrosinase, leading to serious health risks, including nephrotoxicity. Chronic exposure to mercury from cosmetics can harm the liver, kidneys, nervous system, and eyes, with the kidneys being particularly vulnerable. This review discusses the link between fairness creams and the occurrence of glomerular diseases. It delves into the mechanisms by which skin-whitening agents cause kidney damage. Mercury can induce kidney damage through direct cellular toxicity and immune-mediated mechanisms. We present evidence from case studies and published studies connecting mercury-containing creams to nephrotic syndrome. Minimal change disease and membranous nephropathy are the most frequently reported glomerular diseases due to these products. Treatment typically involves stopping the use of the creams and chelation therapy, with glucocorticoids and immunosuppressants for non-responsive cases. The prognosis is generally favourable, with high remission rates, and relapses are seldom reported. By highlighting the nephrotoxic effects of skin-whitening creams, this manuscript emphasizes the urgent need for stringent regulatory oversight and increased public awareness to prevent further health complications.

Relationships between blood concentrations of cadmium, lead, mercury, selenium, and manganese and the risk of chronic kidney disease: a cross-sectional study based on NHANES 2011-2018

Introduction

Currently, knowledge on relationships between blood concentrations of cadmium, lead, mercury, selenium, and manganese and the risk of chronic kidney disease (CKD) is lacking. The aim of the study was to ex-plore the relationships between blood concentrations of heavy metals and the occurrence of CKD.

Material and methods

Data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018 were used to investigate the relationships between blood concentrations of mercury, lead, cadmium, selenium, and manganese and the occurrence of CKD using a weighted logistic recession analysis. Restrictive cubic spline analysis was applied to assess the dose-response relationship. The sample population was divided into four groups based on the quartiles of heavy metal concentrations (Q1: < 25th percentile, Q2: 25th-50th percentile, Q3: 50th-75th percentile, Q4: ≥ 75th percentile).

Results

A total of 15,450 participants were included. With regard to blood lead concentrations, the odds ratio (OR) for CKD in Q4 relative to Q1 was 1.36 (95% confidence interval [CI]: 1.20-1.61), indicating an increased oc-currence of CKD in Q4. With regard to blood cadmium concentrations, the ORs for CKD in Q2, Q3, and Q4 were 1.06 (95% CI: 0.92-1.22), 1.21 (95% CI: 1.05-1.39), and 1.52 (95% CI: 1.31-1.76), respectively. Non-linear dose-response relationships were identified between blood cadmium and lead concentrations and the occurrence of CKD. Further, blood lead and cadmium concentrations showed statistically significant interaction effects with age, hypertension, and obesity on CKD.

Conclusions

Higher cadmium and lead concentrations in blood are asso-ciated with increased occurrence of CKD, especially in older adults, people with hypertension, and people with obesity.

Co-administration of resveratrol rescued lead-induced toxicity in Drosophila melanogaster

Lead toxicity poses a significant environmental concern linked to diverse health issues. This study explores the potential mitigating effects of resveratrol on lead-induced toxicity in Drosophila melanogaster. Adult fruit flies, aged three days, were orally exposed to lead (60 mg/L), Succimer (10 mg), and varying concentrations of resveratrol (50, 100, and 150 mg). The investigation encompassed the assessment of selected biological parameters, biochemical markers, oxidative stress indicators, and antioxidant enzymes. Resveratrol exhibited a dose-dependent enhancement of egg-laying, eclosion rate, filial generation output, locomotor activity, and life span in D. melanogaster, significantly to 150 mg of diet. Most of the investigated biochemical parameters were significantly rescued in lead-exposed fruit flies when co-treated with resveratrol (p < 0.05). However, oxidative stress remained unaffected by resveratrol. The findings suggest that resveratrol effectively protects against lead toxicity in Drosophila melanogaster and may hold therapeutic potential as an agent for managing lead poisoning in humans.

Cabbage juice supplementation abrogates Lead acetate-induced haematological and haemorheological imbalances in male Wistar rat

Lead is a hazardous naturally found heavy metal that has been reported to induce haematological alterations. Whether cabbage, a commonly consumed vegetable rich in antioxidants and anticancer compounds, can mitigate these alterations remains unknown. This study investigated the protective effect of cabbage juice against Lead-induced haematological changes. Twenty (20) male Wistar rats were randomly selected into four groups (n = 5) and given distilled water (1 ml/100 g b.wt), Lead acetate (25 mg/kg b.wt), Cabbage juice (1 ml/100 g b.wt), and Lead acetate with Cabbage juice. All treatments were given orally for 28 days. Lead exposure induces normocytic normochromic anemia with substantial leukocytosis, lymphocytopenia, and hyperfibrinogenemia. Lead-intoxicated animals had significantly higher haemolysis and prolonged clotting times. However, cabbage juice reverses these adverse haematological and haemorheological changes induced by Lead acetate. Conclusively, cabbage juice demonstrated antioxidant, anti-inflammatory, anti-thrombotic, and immunomodulatory properties, as well as the ability to protect the red blood cell membrane from damage caused by Lead-induced osmotic stress.

Impact of plant extracts on hepatic redox metabolism upon lead exposure: a systematic review of preclinical in vivo evidence

The liver is a central target organ of heavy metals toxicity, and secondary metabolites of several plant species are suggested to attenuate lead (Pb)-induced hepatotoxicity through antioxidant and anti-inflammatory mechanisms. We used a systematic review framework to map the impact of plant extracts and bioactive secondary metabolites on immunological markers and liver redox metabolism in preclinical models of Pb exposure. This is a systematic review performed according to PRISMA guidelines. The structured research of publications was done through PubMed, Scopus, Web of Science, and Embase databases, selecting and analyzing 41 original studies included via the eligibility criteria. Evidence indicates that Pb-exposure increases reactive oxygen/nitrogen species (ROS/RNS) production by δ-aminolevulinic acid auto-oxidation, xanthine dehydrogenase, and xanthine oxidase upregulation. Pb exposure also inhibits antioxidant enzymes, potentiating ROS/NOS levels and reactive cell damage. Plant extracts rich in flavonoids, tannins, alkaloids, anthocyanins, and vitamins exerted hepatoprotective effects by chelating and decreasing Pb bioaccumulation. In addition, plant extracts reinforce exogenous and endogenous antioxidant defenses, attenuating liver oxidative stress and cell death. The lack of blinded evaluators and randomized experimental groups were the main sources of bias identified, which need to be controlled in toxicological studies aimed at identifying natural products applied to the prevention or treatment of Pb poisoning.

The Effects of Sodium Tetraborate against Lead Toxicity in Rats: The Behavior of Some Metabolic Enzymes

This study was planned to research the in vivo effects of lead (Pb) ions and sodium tetraborate (Na2B4O7) on G6PD and 6PGD, which are some of the enzymes of the pentose phosphate pathway, which carries vital importance for metabolism, and GR and GST, which are glutathione metabolism enzymes, and the in vitro effects of the same agents on the 6PGD enzyme. According to the in vivo analysis results, in comparison to the control group, the rat liver G6PD (p < 0.05), and 6PGD (p < 0.01) enzyme activities in the Na2B4O7 group were significantly lower. In addition, GR and GST enzyme activities were insignificantly lower in the Na2B4O7 group compared to the control group (p > 0.05). The Pb group had lower G6PD and 6PGD enzyme activity levels and higher GR and GST enzyme activity levels compared to the control group, while these changes did not reach statistical significance (p > 0.05). In the in vitro analyses of the effects of Pb ions on the 6PGD enzyme that was purified out of rat liver with the 2',5'-ADP-Sepharose 4B affinity chromatography method, it was determined that Pb ions (200-1200 μM) increased the rat liver 6PGD enzyme activity levels by 33%. On the other hand Na2B4O7 was not significantly effective on 6PGD activity. These results will also contribute to future studies in understanding the physiopathology of the states triggered by Pb ions and sodium tetraborate (Na2B4O7).

Antioxidants in brain tumors: current therapeutic significance and future prospects

Brain cancer is regarded among the deadliest forms of cancer worldwide. The distinct tumor microenvironment and inherent characteristics of brain tumor cells virtually render them resistant to the majority of conventional and advanced therapies. Oxidative stress (OS) is a key disruptor of normal brain homeostasis and is involved in carcinogenesis of different forms of brain cancers. Thus, antioxidants may inhibit tumorigenesis by preventing OS induced by various oncogenic factors. Antioxidants are hypothesized to inhibit cancer initiation by endorsing DNA repair and suppressing cancer progression by creating an energy crisis for preneoplastic cells, resulting in antiproliferative effects. These effects are referred to as chemopreventive effects mediated by an antioxidant mechanism. In addition, antioxidants minimize chemotherapy-induced nonspecific organ toxicity and prolong survival. Antioxidants also support the prooxidant chemistry that demonstrate chemotherapeutic potential, particularly at high or pharmacological doses and trigger OS by promoting free radical production, which is essential for activating cell death pathways. A growing body of evidence also revealed the roles of exogenous antioxidants as adjuvants and their ability to reverse chemoresistance. In this review, we explain the influences of different exogenous and endogenous antioxidants on brain cancers with reference to their chemopreventive and chemotherapeutic roles. The role of antioxidants on metabolic reprogramming and their influence on downstream signaling events induced by tumor suppressor gene mutations are critically discussed. Finally, the review hypothesized that both pro- and antioxidant roles are involved in the anticancer mechanisms of the antioxidant molecules by killing neoplastic cells and inhibiting tumor recurrence followed by conventional cancer treatments. The requirements of pro- and antioxidant effects of exogenous antioxidants in brain tumor treatment under different conditions are critically discussed along with the reasons behind the conflicting outcomes in different reports. Finally, we also mention the influencing factors that regulate the pharmacology of the exogenous antioxidants in brain cancer treatment. In conclusion, to achieve consistent clinical outcomes with antioxidant treatments in brain cancers, rigorous mechanistic studies are required with respect to the types, forms, and stages of brain tumors. The concomitant treatment regimens also need adequate consideration.

A Comprehensive Review of C. capsularis and C. olitorious: A Source of Nutrition, Essential Phytoconstituents and Pharmacological Activities

Plant bioactive compounds have gained global significance in terms of both medicinal and economic ramifications due to being easily accessible and are believed to be effective with fewer side effects. Growing relevant clinical and scientific evidence has become an important criterion for accepting traditional health claims of medicinal plants and also supports the traditional uses of Corchorus as folk medicine. C. capsularis and C. olitorius have broad applications ranging from textile to biocomposite, and young leaves and shoots are used as healthy vegetables and have long been used as traditional remedies for fever, ascites, algesia, liver disorders, piles, and tumors in many cultures. This review systematically summarized and emphasized the nutritional attributes, mostly available bioactive compounds, and biological and potential pharmaceutical properties of C. capsularis and C. olitorius, disclosed to users and non-users. Results suggest that various phytochemicals such as cardiac glycosides, phenols, flavonoids, sterols, lipids, and fatty acids were found or analytically identified in different plant parts (leaf, stem, seed, and root), and many of them are responsible for pharmacological properties and their antitumor, anticancer, antioxidant, antinociceptive, anti-inflammatory, analgesic, antipyretic, antiviral, antibacterial, anticonvulsant, antidiabetic and antiobesity, and cardiovascular properties help to prevent and cure many chronic diseases. In addition to their use in traditional food and medicine, their leaves have also been developed for skin care products, and some other possible uses are described. From this review, it is clear that the isolated compounds of both species have great potential to prevent and treat various diseases and be used as functional foods. In conclusion, this comprehensive review establishes a significant reference base for future research into various medical and functional food applications.

Antioxidative, anti-inflammatory and anti-apoptotic action of ellagic acid against lead acetate induced testicular and hepato-renal oxidative damages and pathophysiological changes in male Long Evans rats

Lead (Pb), is an environmental toxicant, causes multi-organ dysfunction including reproductive impairments. This study designed to investigate the prospective antioxidative, anti-inflammatory and anti-apoptotic effects of ellagic acid (EA) on Pb-mediated testicular and hepato-renal toxicity. Four experimental groups of five male Long-Evans rats each were used: control, Pb (60 mg/kg), EA (30 mg/kg), and Pb + EA groups. All groups were given their respective treatment orally for 30 days. Pb exposure altered body and organs weight, food and water consumption, rectal temperature, Pb residue levels in tissues, liver and kidney function, sperm quality parameters, serum metabolic and hematology profiles, and impaired the oxidative/antioxidative balance in the testicular and hepato-renal tissue, as shown by the decreased antioxidant proteins (superoxide dismutase, catalase, glutathione peroxidase, and reduced glutathione) and increased the oxidative (MDA, lipid hydroperoxides, conjugated dienes, protein carbonyl, fragmented DNA and GSH:GSSG ratio) stress and inflammatory (IL-1, IL-6, TNF-α, prostaglandin, LTB4, NO, myeloperoxidase, LDH) markers. Moreover, a dysregulation in the stress response (HSP-70) and apoptotic-regulating proteins (BAX, BCL-2, and active Caspase-3) were recorded upon Pb exposure. Remarkably, EA oral administration reduced the Pb residue levels in tissues, improved the liver and kidney function, revived the spermatogenesis and sperm quality, restored redox homeostasis, suppressed the oxidative stress, inflammatory and apoptotic responses in the liver, kidney and testis tissue. Our findings point out that EA can be used as a phyto-chelator to overcome the adverse effects of Pb exposure due to its potent antioxidant, anti-inflammatory, and anti-apoptotic effects.

Lead exposure-induced changes in hematology and biomarkers of hepatic injury: protective role of TrévoTM supplement

Lead exposure has been linked to health challenges involving multiple organ failure. More than fifty percent of lead present in the human body is accumulated in the liver causing hepatic injury. A major mechanism of lead toxicity is oxidative stress. TrévoTM is a nutritional supplement with numerous bioactive natural products with detoxifying and antioxidant properties. This study was designed to investigate the hepatoprotective effects of TrévoTM dietary supplements against lead-hepatotoxicity in male Wistar rats. Thirty-five healthy animals were divided into five groups of seven each as follows: Group I=control; II=15 mg/kg of lead acetate (PbA); III= 2 mL/kg of TrévoTM + PbA; IV= 5 mL/kg of TrévoTM + PbA;V=5 mL/kg of TrévoTM . Animals were orally treated with TrévoTM for two days before co-administration with PbA intraperitoneally for 12 consecutive days. Animals were sacrificed 24 h after the last administration and blood were collected via cardiac puncture and processed for hematological parameters and assessment of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and albumin (ALB). The liver was excised and processed for markers of oxidative stress and histopathological examination. Intraperitoneal administration of 15 mg/kg of PbA caused a significant increase in serum concentration of AST, ALT, while the concentration of ALB was significantly decreased (P<0.001). PbA caused a significant reduction in packed cell volume, hemoglobin while the total white blood cell count, neutrophils, lymphocytes, monocytes, eosinophils, and basophils were increased. Oxidative stress was significantly pronounced in the liver of rats exposed to PbA as observed in the high concentration of malonedialdehyde, decreased concentration of glutathione, the activity of catalase, superoxide dismutase, and glutathione-S-transferase. Pretreatment with TrévoTM was able to significantly prevent the anemic, oxidative damage, and hepatic injury initiated by PbA. Histological examination also corroborated the biochemical results. In conclusion, the study reveals that TrévoTM is effective in attenuating PbA-induced hepatotoxicity in male Wistar rats.

Low-lead doses induce oxidative damage in cardiac tissue: Subacute toxicity study in Wistar rats and Benchmark dose modelling

Exposure to toxic metals, including lead (Pb), were found as important risk factor for cardiovascular diseases. The aim of the study was to simulate low-level subacute Pb exposure scenario and to determine redox status, redox scores (OXY-score, damage score and protective score) and copper (Cu), zinc (Zn), iron (Fe) and manganese (Mn) levels in cardiac tissue of Wistar rats. Based on the obtained results we have established dose-toxic response relationship and derived Benchmark dose. The male Wistar rats were divided in seven groups (n = 6), six threated groups that received 0.1; 0.5; 1; 3; 7; 15 mg Pb/kg body weight/day for 28 days, by oral gavage and control group. The results of the presented study demonstrated that Pb affect cardiac tissue by inducing production of superoxide anion radical (O₂^.-) and consequently raising malondialdehyde (MDA) levels. The positive trend in OXY-score and damage score were determined. Effect size analysis showed that the main toxic effects were oxidative damage and elevation of MDA. The lowest BMD was calculated for MDA (2.2e-0.6 mg Pb/kg b.w./day). Obtained BMD may be useful in further assessing point of departure in the human health risks assessment of low-level Pb exposure scenario.

The influence of erdosteine administration on lead-induced oxidative stress in rat muscle

Lead-exposure is known to disrupt the redox balance of tissues leading to oxidative stress. Due to the fact that a mucolytic drug, erdosteine, exerts also antioxidant properties, we decided to perform a pilot study on rats to evaluate its therapeutic potency in lead poisoning. Male Wistar rats were divided randomly into the following seven groups having 10 animals in each. Group I served as the control group. During 8-week period, rats in groups II-IV, except standard alimentation, received: erdosteine in a dose 350 mg/kg (collateral control group), 1200 ppm of lead acetate in drinking water and placebo, as well as the same doses of lead and erdosteine, respectively. Rats in group V-VII received 1200 ppm of lead acetate in drinking water for the initial 6-week period and then administered: placebo, erdosteine and EDTA for 2 weeks, respectively. The levels of malondialdehyde (MDA) were significantly higher in groups III and V compared to the control group. The activities of catalase (CAT) were significantly higher in groups IV, V, and VI compared to the control group. The activities of glutathione-S-transferase (GST) were significantly lower in group II and significantly higher in groups VI and VII compared to the control group, while the activities of glutathione reductase (GR) were significantly lower in group III and significantly higher in group VI. Erdosteine has an effect of protection against lead-induced oxidative stress which is not worse than that of EDTA.

Oxidative stress, metallomics and blood toxicity after subacute low-level lead exposure in Wistar rats: Benchmark dose analyses

Exposure to lead (Pb) is still rising concern worldwide, having in mind that even low-dose exposure can induce various harmful effects. Thus, in-depth knowledge of the targets of Pb toxicity and corresponding mechanisms is essential. In the presented study, the six groups (male Wistar rats, n = 6) received 0.1; 0.5; 1; 3; 7; 15 mg Pb/kg body weight/day for 28 days, each day by oral gavage, while the control group received distilled water only. All animals were sacrificed 24 h after the treatment, and blood was collected for the analysis of hematological, biochemical, oxidative status and essential elements levels. An external and internal dose-response relationship was performed using PROASTweb 70.1 software. The results showed that low doses of Pb affect hematological parameters and lipid profile after 28 days. The possible mechanisms at examined Pb dose levels were a decrease in SOD, O₂^•- and Cu and an increase in Zn levels. The dose-dependent nature of changes in cholesterol, HDL cholesterol, O₂^.-, SOD, AOPP in serum and hemoglobin, Fe, Zn, Cu in blood were obtained in this study. The most sensitive parameters that were alerted are Cu blood levels (BMDL₅: 1.4 ng/kg b.w./day) and SOD activity (BMDL₅: 0.5 μg/kg b.w./day). The presented results provide information that may be useful in further assessing the health risks of low-level Pb exposure.

Changes in Copper, Zinc, Arsenic, Mercury, and Lead Concentrations in Rat Biofluids and Tissues Induced by the "Renqing Changjue" Pill, a Traditional Tibetan Medicine

The "Renqing Changjue" pill (RQCJ), as an effective prescription of Traditional Tibetan Medicine (TTM), has been widely used in treating advanced gastroenteropathy diseases for over a thousand years. However, the toxicity and adverse effects of TTM have attracted increasing attention because heavy metals may be added as active ingredients. In this work, we introduced a robust model based on endogenous metabolism enabling the study of changes in copper (Cu), zinc (Zn), arsenic (As), mercury (Hg), and lead (Pb) concentrations and the mechanism between biofluids (blood and urine) and tissue (liver, kidney, spleen) samples from rats treated with RQCJ, along with metabolic changes after different treatment time points. Inductively coupled plasma-mass spectrometry was used to monitor the heavy metals. Slightly different trends of heavy metals were observed in rat metabolites. The levels of Hg, As, and Pb were clearly dose-dependent in the tissue and biofluid samples. Basic recovery of Hg and Pb was found after stopping treatment with RQCJ. The accumulation of As was more obvious in the blood, liver, kidney, and spleen; however, Hg was deposited in the kidney. Pb accumulated the most in the spleen. The concentrations of Cu and Zn were constant or accumulated to a certain extent, which could cause the body to have Cu and Zn metabolism disorders in the administration period. Our findings highlight how metal changes and effects on the mechanisms might contribute to the progression of understanding of the toxicity information for RQCJ. Therefore, precautions should be taken in the clinic to monitor the potential toxicity of RQCJ with long-term administration.

Genetic susceptibility of δ-ALAD associated with lead (Pb) intoxication: sources of exposure, preventive measures, and treatment interventions

Delta-aminolevulinic acid dehydratase (δ-ALAD) is involved in the synthesis of haem and exhibits a polymorphic nature. δ-ALAD polymorphism produces two alleles, namely δ-ALAD-1 and δ-ALAD-2, which in turn produce three different phenotypes, namely δ-ALAD1-1, δ-ALAD1-2, and δ-ALAD2-2. δ-ALAD gene is more susceptible to lead (Pb) toxicity than any other genes. Its genotype and phenotype frequencies change with respect to different geographical areas and extent of Pb exposure. The δ-ALAD-2 allele dominancy is linked with high concentration of lead in the body. It has also been thought that the δ-ALAD-2 allele can provoke Pb toxicity by producing a protein that binds more tightly with Pb than δ-ALAD-1 protein. However, few evidences suggest that δ-ALAD-2 may reduce harmful effects by increasing excretion of Pb from the body, thus producing its unavailability towards pathophysiologic alterations. However, the recent evidences have supported that the individuals who are heterozygote for the δ-ALAD-1 allele may be associated with a higher risk of long-term Pb toxicity. In this regard, the individuals who are exposed at occupational levels are among the most frequent study population. The main objective of our study was to explore the gene susceptibility associated with Pb poisoning. Moreover, this study also summarizes various sources of Pb exposure and thereafter outlined multiple strategies to minimize the Pb toxicity in order to save the exposed residential communities.

Myricitrin, a Glycosyloxyflavone in Myrica esculenta Bark Ameliorates Diabetic Nephropathy via Improving Glycemic Status, Reducing Oxidative Stress, and Suppressing Inflammation

The present study evaluated the therapeutic potential of myricitrin (Myr), a glycosyloxyflavone extracted from Myrica esculenta bark, against diabetic nephropathy. Myr exhibited a significant hypoglycemic effect in high fat-fed and a single low-dose streptozotocin-induced type 2 diabetic (T2D) rats. Myr was found to improve glucose uptake by the skeletal muscle via activating IRS-1/PI3K/Akt/GLUT4 signaling in vitro and in vivo. Myr significantly attenuated high glucose (HG)-induced toxicity in NRK cells and in the kidneys of T2D rats. In this study, hyperglycemia caused nephrotoxicity via endorsing oxidative stress and inflammation resulting in the induction of apoptosis, fibrosis, and inflammatory damages. Myr was found to attenuate oxidative stress via scavenging/neutralizing oxidative radicals and improving endogenous redox defense through Nrf-2 activation in both in vitro and in vivo systems. Myr was also found to attenuate diabetes-triggered renal inflammation via suppressing NF-κB activation. Myr inhibited hyperglycemia-induced apoptosis and fibrosis in renal cells evidenced by the changes in the expressions of the apoptotic and fibrotic factors. The molecular docking predicted the interactions between Myr and different signal proteins. An in silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) study predicted the drug-likeness character of Myr. Results suggested the possibility of Myr to be a potential therapeutic agent for diabetic nephropathy in the future.

Late-life Cardiac Injury in Rats following Early Life Exposure to Lead: Reversal Effect of Nutrient Metal Mixture

Early-life exposure to lead (Pb) can lead to health effects in later life. The neurotoxic effects of Pb have been well documented but its effects on the heart are poorly elucidated. We examined the late life cardiac impairments resulting from developmental exposure to Pb. Further, we investigated the protective effect of the nutrient metal mixture containing calcium (Ca), zinc (Zn) and iron (Fe) against Pb-induced long-term effects on cardiac functions.Male albino rats were lactationally exposed to 0.2% Pb-acetate or 0.2% Pb-acetate together nutrient metal mixture as 0.02% in drinking water of the mother from PND 1 to PND 21. The results showed increased levels of serum total cholesterol (TC), triglycerides (TG), low-density lipoproteins (LDLs) and lactate dehydrogenase (LDH) activity at postnatal day (PND) 28 [young], 4 months [adult] and 18 months [old] age group rats. Most notably, exposure to Pb decreased the activities of mitochondrial superoxide dismutase (SOD), thioredoxin reductase (TrxR), aconitase (Acon), isocitrate dehydrogenase (ICDH), xanthine oxidase (XO) and total antioxidant status while the MDA levels increased in all selected age groups of rats. The histological findings showed an age-dependent response to Pb exposure evidenced by extensive degeneration and necrosis in cardiac muscle, disruption in muscle connectivity, hemorrhage, and mononuclear cell infiltration. Co-administration of nutrient metal mixture reversed the Pb-induced cardiac impairments as reflected in the recovery of the chosen sensitive markers of oxidative stress, reduced Pb levels and cardiac tissue changes. In conclusion, the data demonstrate that early-life exposure to Pb continuously influence the cardiac mitochondrial functions from early life to older age and further suggesting that adequate intake of nutrient metals may be potential therapeutic treatment for Pb intoxication.

Ameliorative effect of curcumin against lead acetate-induced hemato-biochemical alterations, hepatotoxicity, and testicular oxidative damage in rats

Lead, toxic heavy metal of global concern, induces toxicity in various organs via oxidative stress. Thereby, in this study, the protective role of curcumin against lead acetate-induced toxicity was evaluated. Thirty-two male albino rats were allocated equally into four groups and orally administered with corn oil as a vehicle (Cont.), curcumin (CUR) (400 mg/kg bw), lead acetate (LA) (100 mg/kg bw), and lead acetate plus curcumin (LA + CUR). All rats had received their treatments daily for 4 weeks. The results revealed that LA toxicity induced normocytic normochromic anemia with significant leukocytosis and lymphocytosis. Moreover, LA-intoxicated rats showed a marked elevation in the liver enzyme activities, serum cholesterol, and triglyceride levels. In contrast, sero-immunological parameters, total protein, albumin, globulin, and testosterone levels were significantly reduced compared to the control rats. Additionally, LA-induced hepatic and testicular oxidative damage revealed by marked increased in MDA level with prominent reduction in the antioxidant system. The gene expression of the hepatic pro-inflammatory markers and testicular steroidogenic biomarkers including LHR and aromatase were significantly upregulated; meanwhile, the expressions of testicular StAR, CYP17a, 3B-HDS, SR-B1, and P450SCC were significantly downregulated in the LA-intoxicated group. Curcumin treatment could partially improve the hematological, biochemical, and histopathological alterations induced by LA. Also, it was observed that curcumin significantly restored hepatic pro-inflammatory markers and testicular steroidogenic enzymes. In conclusion, curcumin has antioxidant, anti-inflammatory, and immunomodulatory effects and is able to minimize the LA-induced oxidative damage in rats.

Luteolin protects against lead acetate-induced nephrotoxicity through antioxidant, anti-inflammatory, anti-apoptotic, and Nrf2/HO-1 signaling pathways

Lead (Pb) is one of the most common heavy metal pollutants affecting living organisms. It induces nephrotoxicity with significant alterations in renal structure and function. Luteolin (LUT) a flavonoid present in various plant products is well known for exhibiting numerous pharmacological properties. We evaluated the protective efficacy of LUT against Pb-induced renal injury in male Wistar rats. Four experimental groups: control, LUT (50 mg/kg, orally), PbAc (20 mg/kg, i.p.), LUT + PbAc (at the aforementioned doses) were maintained for 7 days. PbAc administration significantly increased renal Pb accumulation, urea, and creatinine levels in serum, and induced renal histological alterations. Additionally, compared to the control rats, PbAc-treated rats exhibited significantly low levels of antioxidant enzyme activity and expression (SOD, CAT, GPx and GR), as well as high MDA levels. Moreover, PbAc exposure downregulated Nfe212 and Homx1 mRNA expression and significantly increased inflammatory marker (TNF-α, IL-1β and NO) levels in renal tissue. PbAc significantly upregulated the synthesis of apoptotic related proteins and downregulated antiapoptotic protein expression. Notably, LUT pretreatment of PbAc-treated rats provided significant nephroprotection and reversed the alterations in the abovementioned parameters. In conclusion, LUT provided significant protection against PbAc intoxication via antioxidant, anti-inflammatory, and anti-apoptotic activities by activating the Nrf2/ARE signaling pathway.

Malus micromalus Makino phenolic extract preserves hepatorenal function by regulating PKC-α signaling pathway and attenuating endoplasmic reticulum stress in lead (II) exposure mice

Lead (Pb), which widely recognized as a nonessential heavy metal and a major environmental contamination, is a growing threat to the ecosystem and human body. In the present study, Malus micromalus Makino cv. 'Dong Hong' phenolic extract (MMPE) has been used to antagonise Pb-induced erythrocyte injury, hepatic and renal dysfunction in mice. Six-week-old male Kunming mice were gavaged with PbCl₂ (20 mg/kg mouse/day) and/or MMPE (100 mg/kg mouse/day) by gavage administration for 10 days. We evaluated erythrocyte fragility, relative organ mass, biochemical parameters and histopathological changes to evaluate the protection effect of MMPE on the injury of liver and kidney in Pb-treated mice. MMPE significantly inhibited the increase of protein kinase C-α, B-cell lymphoma-2-associated X, cytochrome C and Caspase-3 protein levels and decreased calreticulin protein expression level in Pb-exposed mice. MMPE supplementation could maintain the integrity of erythrocyte membranes and ameliorate the endoplasmic reticulum stress in Pb-treated mice. It suggested MMPE as a natural nutritional supplement to alleviate Pb-induced hazardous effects in Pb-exposed humans.

Neuromodulatory Activity of Dietary Phenolics Derived from Corchorus olitorius L

Dietary phenolics are known for their potent antioxidant and anti-inflammatory activities, making them promising candidates for protection against neuroinflammation and neurodegeneration. Hydroalcohol extract of Egyptian species of Corchorus olitorius L. (Co) leaves was investigated for its neuroprotective effects in a lipopolysaccharide-induced neuroinflammatory mouse model. Twenty five metabolites were characterized from the bioactive extract using high-performance liquid chromatography HPLC/PDA/HRESI/MSⁿ , revealing 1,5-dicaffeoylquinic acid (Co11) as one of the major constituents (5.7%), which was isolated and its identity was confirmed by spectral data as first report. Co significantly protected microglia against H₂ O₂ -induced cytotoxicity and immunohistochemistry showed reduced expression of the astrocytic marker, glial fibrillary acidic protein, and the inflammatory marker, cyclooxygenase-2. These findings correlated with significant improvement of cognitive functions and reduction of LPS-induced neurodegeneration in Co-treated mice as revealed by histopathology. The current study shows promising effects of Co in limiting neurodegeneration and cognitive impairment caused by neuroinflammation and glial cell activation. PRACTICAL APPLICATION: Information presented here shed light on the promising effects of Corchorus olitorius (Co) for the modulation of neuroinflammatory pathways improving the neuroinflammation-related neurodegeneration and cognitive decline. This makes Co a promising candidate as a nutraceutical supplement to be used against neuroinflammation-related disorders.

Wheat phenolics suppress doxorubicin-induced cardiotoxicity via inhibition of oxidative stress, MAP kinase activation, NF-κB pathway, PI3K/Akt/mTOR impairment, and cardiac apoptosis

The present investigation has been undertaken to reveal the protective mechanism of polyphenolics extract of whole wheat grains (WWGPE), ferulic acid and apigenin against doxorubicin (Dox)-induced cardio-toxicity. WWGPE, apigenin, and ferulic acid exhibited concentration dependent cyto-protective effect against Dox (1 μM) in rat cardiomyocytes. Dox treatment significantly (p < 0.01) induced oxidative stress in the myocardial cells via excessive ROS production, increase in iNOS expression, NADPH oxidase activation, Nrf-2/HO-1 impairment, and inactivation of cellular redox defense system. In addition, Dox significantly (p < 0.01) activated MAP kinases, NF-κB, and apoptosis in cardiac cells; while, significant (p < 0.01) impairment in PI3K/Akt/mTOR signaling was observed in Dox-treated myocardial cells. On the other hand, WWGPE, apigenin, and ferulic acid significantly (p < 0.05-0.01) attenuated Dox-induced redox stress and oxidative stress-mediated signal transduction in myocardial cells. WWGPE, apigenin, and ferulic acid treatment also could significantly (p < 0.05-0.01) reinstate Dox-mediated changes in blood parameters in rats. Histological assessments were in agreement with the biochemical findings. Results showed that, WWGPE exhibited better cardio-protective effect over ferulic acid and apigenin, which may be due to the synergy between the comprising compounds and better oral bioavailability of dietary antioxidant molecules from whole phenolic extract.

Spectroscopic Studies on Dual Role of Natural Flavonoids in Detoxification of Lead Poisoning: Bench-to-Bedside Preclinical Trial

Ubiquitousness in the target organs and associated oxidative stress are the most common manifestations of heavy-metal poisoning in living bodies. While chelation of toxic heavy metals is important as therapeutic strategy, scavenging of increased reactive oxygen species, reactive nitrogen species and free radicals are equally important. Here, we have studied the lead (Pb) chelating efficacy of a model flavonoid morin using steady-state and picosecond-resolved optical spectroscopy. The efficacy of morin in presence of other flavonoid (naringin) and polyphenol (ellagic acid) leading to synergistic combination has also been confirmed from the spectroscopic studies. Our studies further reveal that antioxidant activity (2,2-diphenyl-1-picrylhydrazyl assay) of the Pb-morin complex is sustainable compared to that of Pb-free morin. The metal-morin chelate is also found to be significantly soluble compared to that of morin in aqueous media. Heavy-metal chelation and sustainable antioxidant activity of the soluble chelate complex are found to accelerate the Pb-detoxification in the chemical bench (in vitro). Considering the synergistic effect of flavonoids in Pb-detoxification and their omnipresence in medicinal plants, we have prepared a mixture (SKP17LIV01) of flavonoids and polyphenols of plant origin. The mixture has been characterized using high-resolution liquid chromatography assisted mass spectrometry. The mixture (SKP17LIV01) containing 34 flavonoids and 76 other polyphenols have been used to investigate the Pb detoxification in mouse model. The biochemical and histopathological studies on the mouse model confirm the dual action in preclinical studies.

Dietary strategies to reduce the oral bioaccessibility of cadmium and arsenic in rice

The study aims to seek the dietary strategies to reduce the bioaccessibility of Cd and As in contaminated rice. A total of 12 selected food matrices were assayed by using the in vitro gastrointestinal digestion models. The results showed that tomato, carrot, water spinach, and spinach reduced the solubility of Cd by 45-78%, 50-71%, 53-70%, and 45-71%, respectively. Meanwhile, tomato, carrot, potato, and sweet potato reduced the solubility of As by 53-79%, 50-80%, 40-71%, and 36-76% in aqueous solution, respectively. In both gastric and gastrointestinal phases, Cd and As bioaccessibility decreased as the amount (100, 200, or 400 mg) of food matrices increased (except for As in water spinach). These results suggested that the uses of some foodstuffs may be a good dietary strategy to reduce Cd and As bioaccessibility, although in vivo studies are required to confirm their suitability.

Carnosic Acid, a Natural Diterpene, Attenuates Arsenic-Induced Hepatotoxicity via Reducing Oxidative Stress, MAPK Activation, and Apoptotic Cell Death Pathway

The present studies have been executed to explore the protective mechanism of carnosic acid (CA) against NaAsO₂-induced hepatic injury. CA exhibited a concentration dependent (1–4 μM) increase in cell viability against NaAsO₂ (12 μM) in murine hepatocytes. NaAsO₂ treatment significantly enhanced the ROS-mediated oxidative stress in the hepatic cells both in in vitro and in vivo systems. Significant activation of MAPK, NF-κB, p53, and intrinsic and extrinsic apoptotic signaling was observed in NaAsO₂-exposed hepatic cells. CA could significantly counteract with redox stress and ROS-mediated signaling and thereby attenuated NaAsO₂-mediated hepatotoxicity. NaAsO₂ (10 mg/kg) treatment caused significant increment in the As bioaccumulation, cytosolic ATP level, DNA fragmentation, and oxidation in the liver of experimental mice (n = 6). The serum biochemical and haematological parameters were significantly altered in the NaAsO₂-exposed mice (n = 6). Simultaneous treatment with CA (10 and 20 mg/kg) could significantly reinstate the NaAsO₂-mediated toxicological effects in the liver. Molecular docking and dynamics predicted the possible interaction patterns and the stability of interactions between CA and signal proteins. ADME prediction anticipated the drug-likeness characteristics of CA. Hence, there would be an option to employ CA as a new therapeutic agent against As-mediated toxic manifestations in future.

Antagonistic Effect of Laver, Pyropia yezonensis and P. haitanensis, on Subchronic Lead Poisoning in Rats

Lead, one of the most harmful heavy metals, can cause various hazardous effects on living organisms. This study was undertaken to evaluate the antagonistic and protective effects of two economically important laver species, Pyropia yezoensis and P. haitanensis, against subchronic lead poisoning in rats by a 30-day feeding test. Sixty-four healthy Wistar rats were randomly divided into eight groups with eight rats (4♂ + 4♀) per group, among which, one group was served as the control, the others were respectively treated with lead acetate (5 mg/kg b w), and a combination of lead acetate and P. yezoensis or P. haitanensis at different dosages. Weight gain of rats was observed and recorded. Changes in antioxidant indexes, and liver and renal function markers were determined to evaluate the antagonistic effect. Lead content in rats was determined to investigate lead excretion effect of laver. The results showed that exposure to lead caused lead accumulation in kidney and liver, thus leading to significant oxidative damage and impaired liver and renal function compared to the control group. The co-treatment of laver slightly increased body weight compared to the lead-treated group. The co-administration of laver restored liver and renal function of rats by preventing the increment in the activities of alanine transaminase (ALT), alkaline phosphatase (ALP), and aspartate transaminase (AST), and the levels of blood urea nitrogen (BUN) and creatinine (Cr). The increasing of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities, and lowering of the enhanced malondialdehyde (MDA) contents of rats were observed in the laver co-treated groups, which indicated that laver enhanced the antioxidative capacity of rats. The laver also enhanced lead content in feces and reduced it in liver and kidney. The results indicated that P. yezoensis and P. haitanensis could maintain or promote the normal physiological and biochemical function of lead-induced subchronic poisoning of rats, probably owing to their enhancements of antioxidant capacity and lead excretion.

Effects of Zinc and N-Acetylcysteine in Damage Caused by Lead Exposure in Young Rats

This study investigated the toxicity of rats exposed to lead acetate (AcPb) during the second phase of brain development (8-12 days postnatal) in hematological and cerebral parameters. Moreover, the preventive effect of zinc chloride (ZnCl₂) and N-acetylcysteine (NAC) was investigated. Pups were injected subcutaneously with saline (0.9% NaCl solution), ZnCl₂ (27 mg/kg/day), NAC (5 mg/kg/day) or ZnCl₂ plus NAC for 5 days (3rd-7th postnatal days), and with saline (0.9% NaCl solution) or AcPb (7 mg/kg/day) in the five subsequent days (8th-12th postnatal days). Animals were sacrificed 21 days after the last AcPb exposure. Pups exposed to AcPb presented inhibition of blood porphobilinogen-synthase (PBG-synthase) activity without changes in hemoglobin content. ZnCl₂ pre-exposure partially prevented PBG-synthase inhibition. Regarding neurotoxicity biomarkers, animals exposed to AcPb presented a decrease in cerebrum acetylcholinesterase (AChE) activity and an increase in Pb accumulation in blood and cerebrum. These changes were prevented by pre-treatment with ZnCl₂, NAC, and ZnCl₂ plus NAC. AcPb exposure caused no alteration in behavioral tasks. In short, results show that AcPb inhibited the activity of two important enzymatic biomarkers up to 21 days after the end of the exposure. Moreover, ZnCl₂ and NAC prevented the alterations induced by AcPb.

Thymoquinone ameliorates lead-induced suppression of the antioxidant system in rat kidneys

Objective

Alteration of the antioxidant status in the kidneys may be related to lead (Pb) intoxication. The present study aimed to investigate the possible beneficial effect of thymoquinone (TQ), the major active ingredient of the volatile oil of Nigella sativa seeds, on Pb-induced renal antioxidant defense system impairment.

Methods

A total of thirty two healthy adult male Wistar rats were randomly divided into four equal groups as follows: a control group, which received no treatment; a Pb group, which was exposed to 2,000 ppm of Pb acetate in drinking water; a Pb-TQ group, which was cotreated with Pb plus TQ (5 mg/kg/day, per os); and a TQ group receiving only TQ. All treatments were applied for five weeks.

Results

TQ alone did not induce any significant changes in the antioxidant defense system. By contrast, Pb exposure significantly decreased reduced glutathione level and superoxide dismutase, glutathione peroxidase, catalase, and glutathione reductase activities in the renal tissue. Interestingly, supplementation with TQ significantly improved the affected antioxidant parameters.

Conclusion

Our data are the first to provide evidence on the protective effect of TQ against Pb-induced renal antioxidant capacity impairment and suggest that this component might be a clinically promising alternative in Pb nephrotoxicity.

Chronic Kidney Disease and Exposure to Nephrotoxic Metals

Chronic kidney disease (CKD) is a common progressive disease that is typically characterized by the permanent loss of functional nephrons. As injured nephrons become sclerotic and die, the remaining healthy nephrons undergo numerous structural, molecular, and functional changes in an attempt to compensate for the loss of diseased nephrons. These compensatory changes enable the kidney to maintain fluid and solute homeostasis until approximately 75% of nephrons are lost. As CKD continues to progress, glomerular filtration rate decreases, and remaining nephrons are unable to effectively eliminate metabolic wastes and environmental toxicants from the body. This inability may enhance mortality and/or morbidity of an individual. Environmental toxicants of particular concern are arsenic, cadmium, lead, and mercury. Since these metals are present throughout the environment and exposure to one or more of these metals is unavoidable, it is important that the way in which these metals are handled by target organs in normal and disease states is understood completely.

Berberis vulgaris L. effects on oxidative stress and liver injury in lead-intoxicated mice

Background

Berberis vulgaris L. (BV), commonly known as “Aghriss” in Moroccan pharmacopoeia, is used to cure liver disorders and other diseases. The present study aimed to investigate the protective effect of BV aqueous extract against lead-induced toxicity in mice liver.

Methods

Sixty IOPS mice were divided into six groups and were treated as follows: group 1 (normal control) received double distilled water; group 2 (toxic control) received lead acetate (5 mg/kg body weight/day) in double distilled water for 40 days; groups 3–6 received BV aqueous extract at doses of 25, 50, 100 and 150 mg/kg body weight , respectively, once daily for 30 days from 11 day after beginning of lead acetate exposure to the end of the experiment.

Results

Toxic control group showed a significant alteration of serum alanine-aminotransferase (ALT), aspartate-aminotransferase (AST), total cholesterol (TC), total bilirubin (TB), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and reduced glutathione (GSH). Histological assessment of lead-intoxicated mice liver revealed alterations in hepatocytes and focal necrosis. BV treatment significantly prevented lead accumulation, increased ALT, AST, TC, and TB, inhibited lipid peroxidation and protein carbonyls(PCO) formation. Additionally, BV extract normalized the antioxidant enzymes (CAT, SOD and GPx), GSH and architecture of liver tissues.

Conclusions

BV aqueous extract exerts significant hepatoprotective effects against lead-induced oxidative stress and liver dysfunction. The BV effect may be mediated through the enhancement of antioxidant status, lead-chelating abilities and free radicals quenching.

Toxicological effects of particulate matter (PM2.5) on rats: Bioaccumulation, antioxidant alterations, lipid damage, and ABC transporter activity

Previous studies have demonstrated the harmful effects of atmospheric pollutants on cardiac systems because of the presence of particulate matter (PM), a complex mixture of numerous substances including trace metals. In this study, the toxicity of PM2.5 from two regions, rural (PM2.5 level of 8.5 ± 4.0 μg m(-3)) and industrial (PM2.5 level of 14.4 ± 4.1 μg m(-3)) in Brazil, was investigated through in vivo experiments in rats. Metal accumulation and biochemical responses were evaluated after rats were exposed to three different concentrations of PM2.5 in saline extract (10× dilution, 5× dilution, and concentrated). The experimental data showed the bioaccumulation of diverse trace metals in the hearts of groups exposed to PM2.5 from both regions. Furthermore, mobilization of the antioxidant defenses and an increase in lipid peroxidation of the cardiac tissue was observed in response to the industrial and rural area PM2.5. Glutathione-S-transferase activity was increased in groups exposed to the 5× and concentrated rural PM2.5. Additionally, ATP-binding cassette (ABC) transporter activity in the cardiac tissue exposed to PM2.5 was reduced in response to the 5× dilution of the rural and industrial region PM2.5. Histological analysis showed a decrease in the percentage of cardiac cells in the heart at all tested concentrations. The results indicate that exposure to different concentrations of PM2.5 from both sources causes biochemical and histological changes in the heart with consequent damage to biological structures; these factors can favor the development of cardiac diseases.

Nephrotoxic effects of lead nitrate exposure in diabetic and nondiabetic rats: Involvement of oxidative stress and the protective role of sodium selenite

Heavy metals are known to be toxic to organisms. The present study was undertaken to evaluate the protective effect of sodium selenite against lead nitrate (LN)-induced nephrotoxicity in diabetic and nondiabetic rats. Animals were divided into eight groups where the first was served as a control, whereas the remaining groups were treated with sodium selenite (1 mg/kg b.w.), LN (22.5 mg/kg b.w.) and a combination of LN and sodium selenite and diabetic forms of these groups. Changes in antioxidant enzyme activities, malondialdehide levels, serum urea, uric acid, creatinine levels, body, and kidney weights and histopathological changes were determined after 28 days. LN caused severe histopathological changes, increment in urea, uric acid, creatinine, and MDA levels, also decreasing in antioxidant enzyme activities, body, and kidney weights. In sodium selenite + LN group, we observed the protective effect of sodium selenite on examining parameters. Also diabetes caused alterations on these parameters compared with nondiabetic animals. We found that sodium selenite did not show protective effect on diabetes caused damages. As a result, LN caused nephrotoxicity and sodium selenite alleviated this toxicity but sodium selenite did not protect kidneys against diabetes mediated toxicity. Also, LN caused more harmfull effects in diabetic groups compared with nondiabetic groups. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1229-1240, 2016.

The microscopic and ultramicroscopic changes in the skeletal muscles, caused by heavy metal salts

PURPOSE

The article is devoted to study the structural changes in the skeletal muscles caused by heavy metal salts.

MATERIALS AND METHODS

The study was conducted on 72 mature male rats. The experimental groups were given to drink water with combinations of heavy metal salts for one, two and three months. This type of water is typical for the water basins in the northern districts of the Sumy region. The study of morphological changes in the striated muscles was concluded using light and scanning electron microscopy.

RESULTS

The data analysis revealed that a prolonged duration of negative factor could intensify sclerotic and edematous processes. The structure of muscle fibers was destroyed, nuclei were deformed and placed irregularly, and many petechial hemorrhages occurred. Besides, cross-striation was irregular, I and A bands were deformed and destroyed, H band was hardly visualized. The inner mitochondrial membrane and cristae become deformed. The symplastic nuclei were placed irregularly within sarcoplasm. Besides, they were swollen. Against swollen and enlarged symplastic nuclei, pyknotic nuclei were also found. The structures of sarcoplasmic reticulum were mainly dilated with deformed and ruptured areas.

CONCLUSION

Our study approves that high concentrations of heavy metal salts have a destructive influence on the skeletal striated muscles.

Protective effect of thymoquinone against lead-induced hepatic toxicity in rats

Lead (Pb) intoxication is a worldwide health problem which frequently affects the liver. This study was carried out to investigate the potential protective effect of thymoquinone (TQ), the major active ingredient of volatile oil of Nigella sativa seeds, against Pb-induced liver damage. Adult male rats were randomized into four groups: Control group received no treatment, Pb group was exposed to 2000 ppm Pb acetate in drinking water, Pb-TQ group was cotreated with Pb plus TQ (5 mg/kg/day, per orally), and TQ group receiving only TQ. All treatments were applied for 5 weeks. Results indicated that Pb exposure increased hepatic Pb content, damaged hepatic histological structure (necrotic foci, hepatic strands disorganization, hypertrophied hepatocytes, cytoplasmic vacuolization, cytoplasmic loss, chromatin condensation, mononuclear cell infiltration, congestion, centrilobular swelling), and changed liver function investigated by plasma biochemical parameters (AST, ALT, ALP, γ-GT, LDH). Pb treatment also decreased total antioxidant status level and increased lipid peroxidation in the liver. Supplementation with TQ remarkably improved the Pb-induced adverse effects without significantly reducing the metal accumulation in the liver. In conclusion, our results indicate, for the first time, a protective effect of TQ against Pb-induced hepatotoxicity and suggest that this component might be clinically useful in Pb intoxication.

Prophylactic role of Enhydra fluctuans against arsenic-induced hepatotoxicity via anti-apoptotic and antioxidant mechanisms

OBJECTIVES

The present study was undertaken to evaluate the prophylactic effect of aqueous extract of Enhydra fluctuans (AEEF) against NaAsO2-induced hepatotoxicity.

METHODS

The cytoprotective effect of AEEF against NaAsO2 (10 µM) toxicity was measured on isolated murine hepatocytes. The effect on lipid peroxidation, protein carbonylation, cellular redox markers and signal proteins were measured after incubating the hepatocytes with NaAsO2 (10 µM) + AEEF (400 µg/ml). Finally, the prophylactic effect of AEEF (50 and 100 mg/kg) against NaAsO2 (10 mg/kg) toxicity was measured by in vivo assay in experimental mice.

RESULTS

In vitro bioassay on isolated mouse hepatocytes confirmed cytoprotective effect of AEEF. The NaAsO2 treatment significantly (P<0.01) increased the levels of lipid peroxidation, protein carbonylation with concomitant reduction (P<0.01) of antioxidant enzymes and reduced glutathione levels in hepatocytes. In addition, NaAsO2 significantly (P<0.05-0.01) altered the expression of intrinsic (Bad↑, Bcl-2↓, cleaved-caspase 3↑ and cleaved-caspase 9↑) and extrinsic (Fas↑, Bid↑, cleaved-caspase 8↑) transcription proteins participating in the apoptotic event. However, AEEF treatment could significantly rescue the aforementioned parameters near-normal levels. In in vivo bioassay, NaAsO2 intoxication increased (p<0.01) bioaccumulation of As along with the abnormalities in haematological parameters and redox imbalance in the livers of experimental mice. Treatment with AEEF, however, could significantly (P<0.05-0.01) restore the hematological and redox parameters to the near-normal levels, with histological studies of livers supporting the protective role of AEEF.

DISCUSSION

Presence of substantial quantity of ascorbic acid, phenolics and flavonoids in the extract may be responsible for overall protective effect.

Cytoprotective and Antioxidant Effects of an Edible Herb, Enhydra fluctuans Lour. (Asteraceae), against Experimentally Induced Lead Acetate Intoxication

Background

Enhydra fluctuans Lour. (Asteraceae), an edible aquatic herb, is traditionally employed against toxic effects of heavy metals in India. The present study was planned to discover the protective effect of edible extract of E. fluctuans (AEEF) against Pb toxicity.

Methods

The cytoprotective role of AEEF was determined on murine hepatocytes employing MTT assay and Hoechst staining. The effects on lipid peroxidation, protein carbonylation, endogenous redox systems and the transcription levels of apoptotic proteins were studied after incubating the hepatocytes with AEEF (400 μg/ml) + Pb-acetate (6.8 μM). The defensive role of AEEF (100 mg/kg) against Pb-acetate (5 mg/kg) intoxication was measured in mice by in vivo assays. Biochemical, haematological and histological parameters, intracellular Pb burden and redox status were measured.

Results

AEEF exhibited a concentration dependent cytoprotective effect against Pb-induced cytotoxicity in vitro. Pb-acetate incubation significantly (p < 0.01) altered the extents of ROS production ↑, protein carbonylation ↑, lipid peroxidation ↑, endogenous antioxidant enzymes ↓ and GSH ↓ in vitro. Besides, Pb-acetate significantly (p < 0.01) induced apoptosis in the hepatocytes apparent from the altered expressions of apoptotic proteins viz. Apaf-1 ↑, Bad ↑, Bcl-2 ↓, Cyt C ↑, cleaved caspases↑, Bid ↑ and Fas ↑. However, AEEF (400 μg/ml) could significantly (p < 0.05–0.01) attenuate the Pb-acetate mediated toxic manifestation in vitro. In in vivo assay, Pb-acetate (5 mg/kg) treated mice exhibited significantly (p < 0.01) high intracellular Pb content. A high Pb-burden within the tissues caused significant (p < 0.05–0.01) patho-physiological alterations viz. ROS production ↑, protein carbonylation↑, lipid peroxidation ↑, DNA fragmentation ↑, ATP formation ↑, mitochondrial co-enzymes Q ↓, endogenous antioxidant enzymes ↓ and GSH ↓ within the selected tissues. The haematological and serum biochemical parameters were significantly (p < 0.05–0.01) different in the Pb-acetate treated mice. Finally, histological assessment imposed significant toxic occurrence within the organs of Pb-intoxicated animals. However, concurrent administration of AEEF (100 mg/kg) could significantly (p < 0.05–0.01) reinstate the Pb-acetate mediated toxicity.

Conclusion

Presence of metal chelators and phyto-antioxidants within AEEF would offer overall protection through promoting Pb clearance coupled with restoring redox balance.

Long-Term Exposure of Lead Acetate on Rabbit Renal Tissue

Background:

Lead has been widely used in different industries for ages. It is one of the heavy metals, highly poisonous even at low doses, and has biochemical, physiological and behavioral side effects on human and animals. It has been shown that lead has toxic effects on different tissues such as neural and genitourinary tissues, cardiovascular systems and blood. Therefore, high attention has been paid to its environmental pollutions.

Objectives:

Although many histological and biochemical studies have reported about the effects of lead on the renal tissue, there are a few studies about the ultrastructure and morphometric effects of lead on the kidney. Hence, the aim of this study was the evaluation of morphology and morphometrics of rabbit renal urinary barrier ultrastructure following long-term exposure to lead acetate.

Materials and Methods:

In this experimental study, 20 male New Zealand rabbits were divided into control and test groups (10 in each). The test group was injected intraperitoneally with chronic dose (8.5 mg/kg of body weight) of lead acetate and for the control group the same volume of normal saline was used, every other day for 10 weeks. After anesthetizing, the biopsies of renal tissues were taken for light and electron microscopic morphometric and morphologic analyses.

Results:

Long-term exposure to lead acetate caused histopathology effects including dilatation, congestion, nuclei heterochromatic effects, increase in diameter of renal tubules and urinary barrier thickness in rabbit renal tissue.

Conclusions:

Quantitative and qualitative results of long-term lead acetate exposure showed many histopathology side-effects, especially in the urinary barrier.

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.

The effects of two common edible herbs, Ipomoea aquatica and Enhydra fluctuans, on cadmium-induced pathophysiology: a focus on oxidative defence and anti-apoptotic mechanism

Background

Ipomoea aquatica (Convolvulaceae) and Enhydra fluctuans (Asteraceae), two aquatic vegetables, are traditionally used against heavy metal toxicity in traditional medicines in India. The present study aimed to explore the protective role of edible (aqueous) extracts of I. aquatica (AEIA) and E. fluctuans (AEEF) against Cd-intoxication.

Methods

The extracts were chemically standardized by spectroscopic and HPLC analysis. The cytoprotective roles of AEIA and AEEF were measured on mouse hepatocytes. The effect on redox status were measured after incubating the hepatocytes with CdCl₂ (30 μM) along with AEIA or AEEF (400 μg/ml). The effects on the expressions of apoptotic signal proteins were estimated. The protective roles of AEIA or AEEF were measured by in vivo assay in mice. Haematological, serum biochemical, tissue redox status, Cd bioaccumulation and histological parameters were evaluated to estimate the protective role of AEIA or AEEF (100 mg/kg) against CdCl₂ (4 mg/kg) intoxication.

Results

Phytochemical analysis revealed presence of substantial quantities of phenolics, flavonoids, saponins, carbohydrates and ascorbic acid in AEIA or AEEF. CdCl₂ treated murine hepatocytes showed a gradual reduction of cell viability in a concentration dependent manner with an IC₅₀ of ~30 μM. CdCl₂ treated hepatocytes exhibited significantly enhanced levels (p < 0.01) of ROS production, lipid peroxidation, protein carbonylation and NADPH oxidase with concomitant depletion (p < 0.01) of antioxidant enzymes and GSH. However, AEIA or AEEF treatment along with CdCl₂ significantly restored the aforementioned parameters in murine hepatocytes near to normalcy. Besides, AEIA or AEEF significantly counteracted (p < 0.05–0.01) with ROS mediated alteration of transcription levels of signal proteins viz. Bcl-2, BAD, Cyt-C, Caspases, Fas and Bid. In in vivo bioassay, CdCl₂ treatment caused significantly high Cd bioaccumulation and oxidative stress in the liver, kidney, heart, brain and testes in mice. In addition, the haematological and serum biochemical parameters were significantly altered in the CdCl₂ treated animals. Simultaneous administration of AEIA or AEEF could significantly restore the tested parameters to the near-normal status.

Conclusion

The extracts would offer the overall protective effect via counteracting with Cd mediated oxidative stress and/or promoting the elimination of Cd by chelating.

Effects of lead nitrate and sodium selenite on DNA damage and oxidative stress in diabetic and non-diabetic rat erythrocytes and leucocytes

The adverse effects of lead nitrate (LN) and the preventive role of sodium selenite were investigated in diabetic and non-diabetic rat blood by measuring trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) also by evaluating DNA damage with comet assay. LN increased the levels of MDA, tail DNA%, mean tail length and tail moment, decreased the enzymes activities, FRAP and TEAC values. In sodium selenite+LN group, we observed the protective effect of sodium selenite on examining parameters. Diabetes caused alterations on these parameters, too. We found that sodium selenite did not protect against diabetes caused damages. As a result, LN caused toxic effects on blood cells and sodium selenite alleviated this toxicity but it did not show preventive effect against diabetes. Also, LN caused more harmfull effects in diabetic groups than non-diabetic groups.

Ameliorative effect of water spinach, Ipomea aquatica (Convolvulaceae), against experimentally induced arsenic toxicity

BACKGROUND

Ipomea aquatica (Convolvulaceae) is traditionally used against Arsenic (As) poisoning in folk medicines in India. The present study was designed to explore the therapeutic role of aqueous extract of I. aquatica (AEIA) against As-intoxication.

METHODS

AEIA was chemically standardized by spectroscopic and chromatographic analysis. The cytoprotective role of AEIA was measured on isolated murine hepatocytes. The effect on redox status were measured after incubating the hepatocytes with NaAsO2 (10 μM) + AEIA (400 μg/ml). The protective effect of AEIA (400 μg/ml) in expressions of apoptotic proteins were estimated in vitro. The protective role of AEIA was measured by in vivo assay in mice. Haematological, biochemical, As bioaccumulation and histological parameters were evaluated to ensure the protective role of AEIA (100 mg/kg) against NaAsO2 (10 mg/kg) intoxication.

RESULTS

Phytochemical analysis revealed presence of substantial quantities of phenolics, flavonoids, saponins and ascorbic acid in AEIA. Incubation of murine hepatocytes with AEIA (0-400 μg/ml) + NaAsO2 (10 μM) exerted a concentration dependent cytoprotective effect. Incubation of murine hepatocytes with NaAsO2 (10 μM, ~ IC50) induced apoptosis via augmenting oxidative stress. NaAsO2 treated hepatocytes exhibited significantly (p < 0.01) enhanced levels of ROS production, lipid peroxidation and protein carbonylation with concomitant depletion of antioxidant enzymes (p < 0.05-0.01) and GSH (p < 0.01) levels. However, AEIA (400 μg/ml) + NaAsO2 (10 μM) could significantly (p < 0.05-0.01) reinstate the aforementioned parameters to near-normal status. Besides, AEIA (400 μg/ml) could significantly counteract (p <0.05-0.01) ROS mediated alteration in the expressions of apoptotic proteins viz. Bcl-2, BAD, Cyt C, Apaf 1, caspases, Fas and Bid. In in vivo bioassay, NaAsO2 (10 mg/kg) treatment in mice caused significantly (p < 0.05-0.01) elevated As bioaccumulation, ATP levels, DNA fragmentations and oxidative stress in the liver, kidney, heart, brain and testes along with alteration in cytoarchitecture of these organs. In addition, the serum biochemical and haematological parameters were significantly (p < 0.05-0.01) altered in the NaAsO2-treated animals. However, concurrent administration of AEIA (100 mg/ml) could significantly reinstate the NaAsO2-induced pathogenesis.

CONCLUSION

Presence of substantial quantities of dietary antioxidants within AEIA would be responsible for overall protective effect.

Abroma augusta L. (Malvaceae) leaf extract attenuates diabetes induced nephropathy and cardiomyopathy via inhibition of oxidative stress and inflammatory response

BACKGROUND

Abroma augusta L. (Malvaceae) leaf is traditionally used to treat diabetes in India and Southern Asia. Therefore, current study was performed to evaluate the protective effect of defatted methanol extract of A. augusta leaves (AA) against type 2 diabetes mellitus (T2DM) and its associated nephropathy and cardiomyopathy in experimental rats.

METHODS

Antidiabetic activity of AA extracts (100 and 200 mg/kg, p.o.) was measured in streptozotocin-nicotinamide induced type 2 diabetic (T2D) rat. Fasting blood glucose level (at specific interval) and serum biochemical markers (after sacrifice) were measured. Redox status, transcription levels of signal proteins (NF-κB and PKCs), mitochondria dependent apoptotic pathway (Bad, Bcl-2, caspase cascade) and histological studies were performed in kidneys and hearts of controls and AA treated diabetic rats.

RESULTS

Phytochemical screening of extracts revealed the presence of taraxerol, flavonoids and phenolic compounds in the AA. T2D rats showed significantly (p < 0.01) elevated fasting blood glucose level. Alteration in serum lipid profile and release of membrane bound enzymes like lactate dehydrogenase and creatine kinase, which ensured the participation of hyperlipidemia and cell membrane disintegration in diabetic pathophysiology. T2DM caused alteration in the serum biochemical markers related to diabetic complications. T2DM altered the redox status, decreased the intracellular NAD and ATP concentrations in renal and myocardial tissues of experimental rats. Investigating the molecular mechanism, activation PKC isoforms was observed in the selected tissues. T2D rats also exhibited an up-regulation of NF-κB and increase in the concentrations of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) in the renal and cardiac tissues. The activation of mitochondria dependent apoptotic pathway was observed in renal and myocardial tissues of the T2D rats. However, Oral administration of AA at the doses of 100 and 200 mg/kg body weight per day could reduce hyperglycemia, hyperlipidemia, membrane disintegration, oxidative stress, vascular inflammation and prevented the activation of oxidative stress induced signaling cascades leading to cell death. Histological studies also supported the protective characteristics of AA.

CONCLUSIONS

Results suggest that AA could offer prophylactic role against T2DM and its associated reno- and cardio- toxicity.

Dietary strategies for the treatment of cadmium and lead toxicity

Cadmium (Cd) and lead (Pb) are toxic heavy metals that cause adverse health effects in humans and animals. Chelation therapy, the conventional treatment for heavy metal toxicity, is reported to have a number of safety and efficacy issues. Recent studies have shown that dietary supplements play important roles in protecting against Cd and Pb toxicity. This paper reviews the evidence for protective effects of essential metals, vitamins, edible plants, phytochemicals, probiotics and other dietary supplements against Cd and Pb toxicity and describes the proposed possible mechanisms. Based on these findings, dietary strategies are recommended for people at risk of Cd and Pb exposure. The application of these strategies is advantageous for both the prevention and alleviation of Cd and Pb toxicity, as such supplements can be added easily and affordably to the daily diet and are expected to have very few side effects compared to the chelation therapy.

Lead Intoxication Synergies of the Ethanol-Induced Toxic Responses in Neuronal Cells--PC12

Lead (Pb)-induced neurodegeneration and its link with widespread neurobehavioral changes are well documented. Experimental evidences suggest that ethanol could enhance the absorption of metals in the body, and alcohol consumption may increase the susceptibility to metal intoxication in the brain. However, the underlying mechanism of ethanol action in affecting metal toxicity in brain cells is poorly understood. Thus, an attempt was made to investigate the modulatory effect of ethanol on Pb intoxication in PC12 cells, a rat pheochromocytoma. Cells were co-exposed to biological safe doses of Pb (10 μM) and ethanol (200 mM), and data were compared to the response of cells which received independent exposure to these chemicals at similar doses. Ethanol (200 mM) exposure significantly aggravated the Pb-induced alterations in the end points associated with oxidative stress and apoptosis. The finding confirms the involvement of reactive oxygen species (ROS)-mediated oxidative stress, and impairment of mitochondrial membrane potential, which subsequently facilitate the translocation of triggering proteins between cytoplasm and mitochondria. We further confirmed the apoptotic changes due to induction of mitochondria-mediated caspase cascade. These cellular changes were found to recover significantly, if the cells are exposed to N-acetyl cysteine (NAC), a known antioxidant. Our data suggest that ethanol may potentiate Pb-induced cellular damage in brain cells, but such damaging effects could be recovered by inhibition of ROS generation. These results open up further possibilities for the design of new therapeutics based on antioxidants to prevent neurodegeneration and associated health problems.

Mitigation of lead-induced neurotoxicity by the naringin: erythrocytes as neurons substitute markers

This study aimed to investigate the effect of lead (Pb) on neuronal nitric oxide synthase (nNOS) activity using erythrocytes as neurons surrogate markers. Moreover, the protective effect of naringin (NAR) against lead acetate (PbAc)-induced neurotoxicity was investigated. Human erythrocytes were incubated with L-arginine (L-Arg), Nω-nitro-L-Arginine methyl ester ( L-NAME), NAR, PbAc, PbAc+L-Arg, PbAc+NAR, or PbAc+L-Arg+NAR. The present results revealed that incubation of erythrocytes with PbAc inhibited NOS activity and decreased nitrite levels as an index for nitric oxide (NO) production to values similar that of L-NAME as known NOS inhibitor. Likewise, PbAc induced a significant decrease in activities of ATPases and acetylcholinesterase compared to control cells. Furthermore, PbAc exposure significantly increased protein carbonyl content (PCC) and malondialdehyde (MDA) levels while significantly decrease the levels of reduced glutathione (GSH). On the contrary, incubation of erythrocytes with PbAc in the presence of L-Arg+NAR synergistically ameliorated the investigated parameters compared to erythrocytes incubated with PbAc alone. These data suggest that NAR can restore NO bioavailability in a situation of Pb-induced cellular damage. This attributed to antioxidant activity and restoration NOS activity.

Neuroprotective effects of xanthone derivative of Garcinia mangostana against lead-induced acetylcholinesterase dysfunction and cognitive impairment

Lead poisoning is a common environmental toxicity and low level of lead exposure is responsible for neurobehavioral or intelligence defects. This study was designed to investigate the protective effect of a xanthone derivative of Garcinia mangostana against lead-induced acetycholinesterase (AChE) dysfunction and cognitive impairment in mice. ICR mice were exposed to lead acetate (Pb) in drinking water (1%) with or without xanthone co-administration (100 and 200mg/kgBW/day) for 38days. Xanthone possesses a high phenolic content, which is positive correlation with its antioxidant activity (R(2)=0.98). The IC50 of xanthone on scavenging free radical activities, hydroxyl radical, superoxide radical, hydrogen peroxide and nitric oxide in cell-free system were 0.48±0.08, 1.88±0.09, 2.20±0.03 and 0.98±0.40mg/mL, respectively. We found that Pb induced AChE dysfunction and memory deficit in a dose dependent manner, indicated by in vitro and in vivo studies. However, xanthone significantly restored AChE activity in the blood and brains of mice and prevented Pb-induced neurobehavioral defect indicators with Forced Swimming and Morris water maze tests. Xanthone treatment improved all indicators compared to the Pb-treated group. In conclusion, xanthone alleviates Pb-induced neurotoxicity, in part, by suppression of oxidative damage and reversing AChE activity with a reduction in learning deficit and memory loss.