Disorders of the Reproductive Health of Cattle as a Response to Exposure to Toxic Metals

Effect of Gentianella acuta (Michx.) Hulten against the arsenic-induced development hindrance of mouse oocytes

The current study was designed to investigate the alleviative effect of Gentianella acuta (Michx.) Hulten (G. acuta) against the sodium arsenite (NaAsO2)-induced development hindrance of mouse oocytes. For this purpose, the in vitro maturation (IVM) of mouse cumulus-oocyte complexes (COCs) was conducted in the presence of NaAsO2 and G. acuta, followed by the assessments of IVM efficiency including oocyte maturation, spindle organization, chromosome alignment, cytoskeleton assembly, cortical granule (CGs) dynamics, redox regulation, epigenetic modification, DNA damage, and apoptosis. Subsequently, the alleviative effect of G. acuta intervention on the fertilization impairments of NaAsO2-exposed oocytes was confirmed by the assessment of in vitro fertilization (IVF). The results showed that the G. acuta intervention effectively ameliorated the decreased maturation potentials and fertilization deficiency of NaAsO2-exposed oocytes but also significantly inhibited the DNA damages, apoptosis, and altered H3K27me3 expression level in the NaAsO2-exposed oocytes. The effective effects of G. acuta intervention against redox dysregulation including mitochondrial dysfunctions, accumulated reactive oxygen species (ROS) generation, glutathione (GSH) deficiency, and decreased adenosine triphosphate (ATP) further confirmed that the ameliorative effects of G. acuta intervention against the development hindrance of mouse oocytes were positively related to the antioxidant capacity of G. acuta. Evidenced by these abovementioned results, the present study provided fundamental bases for the ameliorative effect of G. acuta intervention against the meiotic defects caused by the NaAsO2 exposure, benefiting the future application potentials of G. acuta intervention in these nutritional and therapeutic research for attenuating the outcomes of arseniasis.

Recent Advancements in Fluorometric and Colorimetric Detection of Cd2+ Using Organic Chemosensors: A Review (2019-2024)

In recent decades, heavy metal ions have emerged as a significant global environmental concern, posing threats to the delicate balance of ecosystems worldwide. Their introduction into ecosystems occurs through various activities and poses a serious risk to human health. Among heavy metal ions, Cd2+ is recognized as a highly toxic pollutant. Its widespread use contributes to its accumulation in the environment. Chronic exposure to Cd2+ ions present serious risks to both the environment and human health. Therefore, the detection of these metal ions are very important. Organic fluorometric and colorimetric detection have emerged as promising tools for this purpose, offering advantages such as high sensitivity, selectivity, and sometimes reversibility. This review offers a comprehensive overview of the recent advancements in the fluorometric and colorimetric detection of Cd2+ using organic chemosensors from 2019 to 2024. We delve into key aspects of these studies, including the design strategies employed to design novel chemosensors and the underlying sensing mechanisms. Furthermore, we explore the diverse applications of these organic chemosensors, ranging from environmental monitoring to biomedical diagnostics. By analyzing the latest research findings, this review aims to offer insights into the current state-of-the-art in the field of Cd2+ detection using organic chemosensors. Additionally, it highlights the potential opportunities and challenges that lie ahead, paving the way for future advancements in this important area of research.

Potentially toxic elements in soil-plant-water-animal continuum in a mining area from Northwestern Mexico: animal exposure pathways and health risks for children

Mining increases environmental concentrations of potentially toxic elements (PTEs) accumulating in organisms and spreading in the human food chain-their presence in milk is of great human health concern. Pathways were identified by which these elements reach raw milk from farms within a mining area in Northwestern Mexico; health risks for dairy cattle and children were also evaluated. Water from river and cattle waterers, as well as, soils showed that PTE concentrations generally below the Mexican and international limits; cattle forage concentrations were above the World Health Organization limits. Al, Mg, Mo, Ni and Zn were recorded in raw milk samples from the mining area, showing that Cd, Co, Cr, Cu, Pb and V are transferred from soil to plants but not accumulated in raw milk. Zn concentrations in raw milk exceeded the permissible limit; milk from farms without mining operations (comparison site) showed the presence of Al, Cr and Cu. In cattle tail hair, PTE did not correlate with raw milk concentrations. Metal accumulation in milk was higher through water consumption than that accumulated through forage consumption. Daily intakes (DI) of Al, Mg and Zn in cows could represent a risk for their health. The observed biotransference was higher than in other parts of Mexico, and the calculated DI and hazard quotients indicate no adverse health effects for children. However, the hazard Index values indicate that exposure to multiple PTE represents a risk for children. Management measures should be performed to control the cumulative risks to protect young children's health.

Impact of grazing around industrial areas on milk heavy metals contamination and reproductive ovarian hormones of she-camel with assessment of some technological processes on reduction of toxic residue concentrations

Heavy metals are one of the most toxic chemical pollutants of the environment. Their hazards not restricted to human but extend to animal productivity and reproductively. The present study aimed to assess the impact of grazing around industrial areas on the levels of copper (Cu) and aluminum (Al) residues in milk samples collected from dromedary she-camels and studying their effects on some ovarian hormones. In addition, the study aimed to investigate methods of removal of the toxic concentrations of these heavy metals in milk by applying different technological processes. Blood and milk samples were collected from 30 dromedary she-camels, 15 grazing in non-industrial areas (group A) and 15 grazing in industrial areas (group B). Detection of the levels of these heavy metals in milk was done. Ovarian hormones investigation on the blood was performed. Different technological processes such as boiling, skimming and fermentation were applied to all contaminated samples to reduce the toxic concentrations of these heavy metals. Results revealed that all examined milk samples in both groups contained Cu, while 40% of group A and 100 % of group B contained Al residues with different concentrations. The levels of Cu and Al residues in samples of group A not exceeded the maximum residual limit (MRL) set by World Health Organization (WHO) while 60% and 100% of milk samples in group B contained Cu and Al residues exceeded MRL, respectively. Technological processes induce variant changes in the levels of these metals in milk. Heat treatment of milk in Al vats leads to leaching of Al from containers to the milk causing significant increase in Al load, while Cu level was not significantly affected. Boiling in stainless-steel containers decreased the levels of Al and Cu but in non-significant levels. Regarding skimming process, small amount of Cu and Al escaped into the skimmed milk while greater amount were recovered in the cream. Fermentation by probiotic bacteria showed that milk fermentation has non-significant effect on Cu and Al levels. Investigation of ovarian hormones (estrogen and progesterone) revealed presence of a signification reduction in the levels of these hormones in group B compared to group A. In addition, a negative correlation was found between these heavy metals and ovarian hormones concentrations in the blood. It is concluded that grazing of dromedary camels around industrial areas induce heavy metals toxicity represented by excretion of these metals in milk and significant reduction on ovarian function showed by reduction of estrogen and progesterone levels. Technological processes such as skimming decreased the levels of Al and Cu residues in milk.

Urbanisation threats to dairy cattle health: Insights from Greater Bengaluru, India

Complex urbanisation dynamics, on the one hand, create a high demand for animal products, and on the other hand put enormous pressure on arable land with negative consequences for animal feed production. To explore the impact of accelerated urbanisation on dairy cattle health in urban farming systems, 151 farmers from different parts of the Greater Bengaluru metropolitan area in India were individually interviewed on aspects addressing cattle management and cattle health. In addition, 97 samples of forages from the shores of 10 different lakes, and vegetable leftovers used in cattle feeding were collected for nutritional analysis. Along with the use of cultivated forages, crop residues, and concentrate feed, 47% and 77% of the farmers occasionally or frequently used lake fodder and food leftovers, respectively. Nutritionally, lake fodder corresponded to high-quality pasture vegetation, but 43% of the samples contained toxic heavy metals such as arsenic, cadmium, chromium, and lead above official critical threshold levels. Therefore, lake fodder may affect cows' health if consumed regularly; however, heavy metal concentrations varied between lakes (P < 0.05), but not between fodder types (P > 0.05). Although 60% of the interviewed farmers believed that their cows were in good health, logit model applications revealed that insufficient drinking water supply and the use of lake fodder negatively impacted cattle health (P < 0.05). While it remains unknown if regular feeding of lake fodder results in heavy metal accumulation in animal products, farmers and farm advisors must address this and other urbanization-related challenges to protect cattle health.

Impact and mitigation of lead, cadmium and micro/nano plastics in fragrant rice

Heavy metals (HMs) and micro(nano)plastics (MNPs), represent a significant risk to global food supply as well as a potential risk to humankind. Over 50% of the worldwide population eat rice every day, and rice aroma is a significant qualitative trait that is highly valued by consumers and fetches premium prices in the global market. Despite the huge commercial importance of fragrant rice, limited studies were directed to investigate the influence of HMs and MNPs on yield related traits and 2-Acetyl-1-pyrroline (2-AP) compound, mainly responsible for aroma production in fragrant rice. In this review, we found that the interaction of HMs and MNPs in fragrant rice is complex and accumulation of HMs and MNPs was higher in root as compared to the grains. Nutrients and phytohormones mediated mitigation of HMs and MNPs were most effective sustainable strategies. In addition, monitoring the checkpoints of 2-AP biosynthesis and its interaction with HMs and MNPs is challenging. Finally, we explained the potential challenges that fragrant rice faces considering the continuous rise in environmental pollutants and discussed the future avenues of research to improve fragrant rice's yield and qualitative traits.

Sulforaphane suppresses paraquat-induced oxidative damage in bovine in vitro-matured oocytes through Nrf2 transduction pathway

Sulforaphane (SFN), a bioactive phytocompound extracted from cruciferous plants, has received increasing attention due to its vital cytoprotective role in eliminating oxidative free radical through activation of nuclear factor erythroid 2-related factor (Nrf2)-mediated signal transduction pathway. This study aims at a better insight into the protective benefit of SFN in attenuating paraquat (PQ)-caused impairment in bovine in vitro-matured oocytes and the possible mechanisms involved therein. Results showed that addition of 1 μM SFN during oocyte maturation obtained higher proportions of matured oocytes and in vitro-fertilized embryos. SFN application attenuated the toxicological effects of PQ on bovine oocytes, as manifested by enhanced extending capability of cumulus cell and increased extrusion proportion of first polar body. Following incubation with SFN, oocytes exposed to PQ exhibited reduced intracellular ROS and lipid accumulation levels, and elevated T-SOD and GSH contents. SFN also effectively inhibited PQ-mediated increase in BAX and CASPASE-3 protein expressions. Besides, SFN promoted the transcription of NRF2 and its downstream antioxidative-related genes GCLC, GCLM, HO-1, NQO-1, and TXN1 in a PQ-exposed environment, indicating that SFN prevents PQ-caused cytotoxicity through activation of Nrf2 signal transduction pathway. The mechanisms underlying the role of SFN against PQ-induced injury included the inhibition of TXNIP protein and restoration of the global O-GlcNAc level. Collectively, these findings provide novel evidence for the protective role of SFN in alleviating PQ-caused injury, and suggest that SFN application may be an efficacious intervention strategy against PQ cytotoxicity.

SIRT1/PGC-1α is involved in arsenic-induced male reproductive damage through mitochondrial dysfunction, which is blocked by the antioxidative effect of zinc

Exposure to arsenic poses threats to male reproductive system, including impairing the testes and sperm quality. Although an association regarding arsenic exposure and male reproductive damage has been reported, the undergoing molecular mechanisms and interventions for prevention remain unclear. For the present work, male mice were exposed to 0, 2.5, 5, or 10 ppm sodium arsenite (NaAsO₂) for 8 months. The results showed that arsenic-exposed mice had reduced fertility with abnormalities in the testes, epididymides, and sperm. Exposure of mice to arsenic caused a redox imbalance, decreased SIRT1 and PGC-1α levels, and affected mitochondrial biogenesis and proteins related to mitochondrial dynamics. For immortalized spermatogenic (GC-2) cells, arsenic caused apoptosis and oxidative stress, reduced SIRT1/PGC-1α levels and ATP production, inhibited mitochondrial respiration, and changed the mitochondrial membrane potential (MMP). Mitochondrial biogenesis and dynamics were also impaired. However, by reducing mitochondrial damage in GC-2 cells, upregulation of SIRT1 or zinc (Zn) supplementation reversed the apoptosis induced by arsenic. For mice, Zn supplementation blocked arsenic-induced oxidative stress, the decreases of SIRT1 and PGC-1α levels, and the impairment of mitochondrial function, and it reversed the damage to testes, low sperm quality, and low litter size. Collectively, these results suggest that arsenic causes excessive production of ROS, inhibits the SIRT1/PGC-1α pathway, and causing mitochondrial dysfunction by mediating impairment of mitochondrial biogenesis and dynamics, which results in germ cells apoptosis and male reproductive damage, processes that are blocked by Zn via an antioxidative effect. Our study contributes to understanding of the mechanisms for arsenic-induced male reproductive damage and points to the therapeutic significance of Zn.

Arsenic exposure and its implications in male fertility

Arsenic exposure is a global health concern. This toxic metalloid is ubiquitous in the environment and contaminates food and drinking water. Once ingested, it undergoes a complex metabolic process within the body, which contributes to its accumulation and reactivity. Arsenic toxicity stems from the induction of oxidative stress, inhibition of thiol-containing proteins, and mimicry of inorganic phosphates. Arsenic poisoning is associated with the development of reproductive disorders. In males, arsenic causes a reduction in testicular weight and alterations in steroidogenesis and spermatogenesis. Moreover, it reduces the number and quality of spermatozoa harvested from the cauda epididymis. The mitochondria are targets of arsenic toxicity because of the production of free radicals and their high content of cysteine-rich proteins and fatty acids. Mitochondrial dysfunction may contribute to reproductive disorders because this organelle is crucial for controlling testicular and epididymal events related to sperm production and maturation. All of these alterations mediated by arsenic exposure contribute to the failure of male reproductive competence by reducing gamete viability. This review describes the potential mechanisms of arsenic toxicity, its detrimental effects on male reproductive organs, and consequences on sperm fertility.

Heavy Metal(loid) Accumulation in the Ovarian Tissue of Free-Ranging Queens and Bitches Inhabiting Highly Polluted Urban Environments

There is strong scientific evidence that exposure to environmental contaminants, such as heavy metal(loid)s (HMs), can impair female reproductive function. Pets, such as cats and dogs, who share the same habitat as humans, may be particularly useful sentinel models for detecting HMs in the ovary. In the present study, we compared the concentration of essential (Ems; Cu, Fe, Mn, Se, and Zn) and non-essential metal(loid)s (NEMs; Al, As, Cd, and Pb) in the ovarian tissues of free-ranging queens and bitches of different ages living in industrialized/highly polluted (south group) and non-polluted (north group) urban areas of the island of Sardinia, Italy. The results showed that both EMs and NEMs were present at detectable concentrations in feline and canine ovaries and their levels varied according to geographical areas and animal age. Among the EMs, Cu was found elevated in older queens and bitches inhabiting the southern area. Cadmium and lead were higher in feline and canine ovaries of older animals from the south compared to those living in the north. In addition, Cd and Pb concentrations increased in individuals of both species living in the south. These findings showed new perspectives for the use of pets as early warning sentinels of environmental pollution by HMs and for the risk of human exposure within a "One Health" approach. Pets may help to study the link between exposure to metals and female reproductive disturbances in mammals.

Gestational lead exposure and its effects on fetal/infant development - A systematic review

Studies suggest that gestational exposure to lead (Pb) is related to spontaneous abortions, preterm birth, lower infant birth weight and length, and neurological dysfunctions. However, the evidence about its effects during pregnancy exposure on fetal and child development is still poor. Thus, the aim of this systematic review was to verify the association between prenatal exposure to Pb and the occurrence of neurobehavioral deficits, miscarriages, and child mortality. Observational studies with pregnant women exposed to Pb during pregnancy were included, without gender or ethnicity restrictions. The MEDLINE, Cochrane Library, EMBASE, Scopus, Web of Science, and LILACS databases were searched. The reading of titles and abstracts was conducted, followed by reading in full format and data extraction, that were performed independently by two reviewers. The included studies were evaluated by Downs and Black tool and qualitatively synthesized. Certainty of evidence was assessed by Grading of Recommendations Assessment, Development, and Evaluations (GRADE). The study protocol was registered with the Prospective Registry of Systematic Reviews (PROSPERO; CRD42022296750). Among twenty-one studies included, sixteen were classified as prospective cohort, two case-control, one nested case-control, one cohort, and one longitudinal study. No study that evaluated child mortality associated with gestational Pb exposure was found. There is a very low certainty of evidence in the association of gestational Pb exposure and neurobehavioral deficits or miscarriages. This systematic review reflects the poor evidence and the challenges of human toxicology studies, since it was not possible to associate gestational Pb exposure to neurobehavioral deficits, miscarriages, and child mortality.

Cumulus Cell Transcriptome after Cumulus-Oocyte Complex Exposure to Nanomolar Cadmium in an In Vitro Animal Model of Prepubertal and Adult Age

Cadmium (Cd), a highly toxic pollutant, impairs oocyte fertilization, through oxidative damage on cumulus cells (CCs). This study analysed the transcriptomic profile of CCs of cumulus-oocyte complexes (COCs) from adult and prepubertal sheep, exposed to Cd nanomolar concentration during in vitro maturation. In both age-groups, CCs of matured oocytes underwent RNA-seq, data analysis and validation. Differentially expressed genes (DEGs) were identified in adult (n = 99 DEGs) and prepubertal (n = 18 DEGs) CCs upon Cd exposure. Transcriptomes of adult CCs clustered separately between Cd-exposed and control samples, whereas prepubertal ones did not as observed by Principal Component Analysis. The transcriptomic signature of Cd-induced CC toxicity was identified by gene annotation and literature search. Genes associated with previous studies on ovarian functions and/or Cd effects were confirmed and new genes were identified, thus implementing the knowledge on their involvement in such processes. Enrichment and validation analysis showed that, in adult CCs, Cd acted as endocrine disruptor on DEGs involved in hormone biosynthesis, cumulus expansion, regulation of cell signalling, growth and differentiation and oocyte maturation, whereas in prepubertal CCs, Cd affected DEGs involved in CC development and viability and CC-oocyte communications. In conclusion, these DEGs could be used as valuable non-invasive biomarkers for oocyte competence.

As3MT-mediated SAM consumption, which inhibits the methylation of histones and LINE1, is involved in arsenic-induced male reproductive damage

Studies have demonstrated that arsenic (As) induces male reproductive injury, however, the mechanism remains unknown. The high levels of arsenic (3) methyltransferase (As3MT) promote As-induced male reproductive toxicity. For As-exposed mice, the germ cells in seminiferous tubules and sperm quality were reduced. Exposure to As caused lower S-adenosylmethionine (SAM) and 5-methylcytosine (5 mC) levels, histone and DNA hypomethylation, upregulation of long interspersed element class 1 (LINE1, or L1), defective repair of double-strand breaks (DSBs), and the arrest of meiosis, resulting in apoptosis of germ cells and lower litter size. For GC-2spd (GC-2) cells, As induced apoptosis, which was prevented by adding SAM or by reducing the expression of As3MT. The levels of LINE1, affected by SAM content, were involved in As-induced apoptosis. Furthermore, folic acid (FA) and vitamin B12 (VB₁₂) supplements restored SAM, 5 mC, and LINE1 levels and blocked impairment of spermatogenesis and testes and lower litter size. Exposed to As, mice with As3MT knockdown showed less impairment of spermatogenesis and testes and greater litter size compared to As-exposed wild-type (WT) mice. Thus, the high As3MT levels induced by As consume SAM and block histone and LINE1 DNA methylation, elevating LINE1 expression and evoking impairment of spermatogenesis, which causes male reproductive damage. Overall, we have found a mechanism for As-induced male reproductive damage, which provides biological insights into the alleviation of reproductive injury induced by environmental factors.

Exposure to lead and dietary furan intake aggravates hypothalamus-pituitary-testicular axis toxicity in chronic experimental rats

Lead (Pb) and furan are toxic agents, and persistent exposure may impair human and animal reproductive function. We therefore explored the effects of Pb and furan on male rat hypothalamic-pituitary-gonadal reproductive status, oxidative stress, inflammation, and genomic integrity. We found that co-exposure to Pb and furan reduced the activities of testicular function enzymes, endogenous antioxidant levels, total sulfhydryl group, and glutathione. Sperm abnormality, biomarkers of oxidative stress, inflammation, and p53 expression were increased in a dose-dependent manner by treatment with furan and Pb. Typical rat gonad histoarchitecture features were also damaged. Conclusively, co-exposure to Pb and furan induced male reproductive function derangement by decreasing the antioxidant defences in rats, increasing abnormalities in spermatozoa morphology, and reducing reproductive hormone in circulation. These pathophysiological alterations, if persistent, might provide a permissive environment for potentiating reproductive dysfunction and infertility.

Sperm Quality Affected by Naturally Occurring Chemical Elements in Bull Seminal Plasma

This study monitored the chemical and biochemical composition of bovine seminal plasma (SP). Freshly ejaculated semen (n = 20) was aliquoted into two parts. The first aliquot was immediately assessed to determine the sperm motion parameters. Another motility measurement was performed following an hour-long co-incubation of spermatozoa with SP at 6 °C. The other aliquot was processed to obtain the SP. Seminal plasma underwent the analyses of chemical composition and quantification of selected proteins, lipids and RedOx markers. Determined concentrations of observed parameters served as input data to correlation analyses where associations between micro and macro elements and RedOx markers were observed. Significant correlations of total oxidant status were found with the content of Cu and Mg. Further significant correlations of glutathione peroxidase were detected in relation to Fe and Hg. Furthermore, associations of chemical elements and RedOx markers and spermatozoa quality parameters were monitored. The most notable correlations indicate beneficial effects of seminal Fe on motility and Mg on velocity and viability of spermatozoa. On the contrary, negative correlations were registered between Zn and sperm velocity and seminal cholesterol content and motility. Our findings imply that seminal plasma has a prospective to be developed as the potential biomarker of bull reproductive health.

Protective effect of resveratrol against cadmium-induced toxicity on ovine oocyte in vitro maturation and fertilization

Background

Heavy metal cadmium (Cd) is a widespread environmental contaminant with a potential toxicity that might negatively affect female reproduction and fertility. It has been reported that Cd exposure impaired the quality of oocytes and led to a defective maturation and fertilization, through oxidative stress induction. Resveratrol (Res) is a natural polyphenol with strong antioxidant properties that exhibited protective role in preventing oocyte redox homeostasis disruption and quality decline. Here, we explored whether the addition of Res to in vitro maturation (IVM) medium might act as a protection against Cd-induced toxicity on ovine oocyte maturation and fertilization. Firstly, we evaluated the effect of supplementing IVM medium with two different Res concentrations (1 and 2 μmol/L) on nuclear maturation and fertilization of oocytes matured under CdCl₂ (2 μmol/L) exposure. Therefore, the concentration of 1 μmol/L Res was selected to analyse the effects of this compound on intracellular ROS levels, mitochondrial (mt) distribution and activity, chromatin configuration, cytoskeleton morphology, cortical granules (CGs) distribution and mRNA expression of genes associated with cellular response to oxidative stress (i.e. SIRT1, SOD 1, GPX1, GSR, CAT) in Cd-exposed in vitro matured oocytes.

Results

We found that 1 μmol/L Res restored the reduced oocyte meiotic competence induced by Cd exposure as well as, Res sustained oocyte ability to be normally fertilized and decreased polyspermic fertilization at both tested concentrations. Moreover, we demonstrated that 1 μmol/L Res mitigated Cd-induced alterations of oocyte cytoplasmic maturation by reducing reactive oxygen species (ROS) accumulation, preventing mt dysfunction, maintaining the correct meiotic spindle and cortical F-actin assembly and the normal cortical granule distribution as well as up-regulating SIRT1, SOD1 and GPX1 genes.

Conclusions

Taken together, our findings highlighted the beneficial influence exerted by Res in preventing Cd-induced disturbance of nuclear and cytoplasmic maturation and subsequent fertilization in ovine oocytes. Res treatment may help to establish defence strategies counteracting Cd-induced toxicity on the female gamete.

Mixed Contaminants: Occurrence, Interactions, Toxicity, Detection, and Remediation

The ever-increasing rate of pollution has attracted considerable interest in research. Several anthropogenic activities have diminished soil, air, and water quality and have led to complex chemical pollutants. This review aims to provide a clear idea about the latest and most prevalent pollutants such as heavy metals, PAHs, pesticides, hydrocarbons, and pharmaceuticals—their occurrence in various complex mixtures and how several environmental factors influence their interaction. The mechanism adopted by these contaminants to form the complex mixtures leading to the rise of a new class of contaminants, and thus resulting in severe threats to human health and the environment, has also been exhibited. Additionally, this review provides an in-depth idea of various in vivo, in vitro, and trending biomarkers used for risk assessment and identifies the occurrence of mixed contaminants even at very minute concentrations. Much importance has been given to remediation technologies to understand our current position in handling these contaminants and how the technologies can be improved. This paper aims to create awareness among readers about the most ubiquitous contaminants and how simple ways can be adopted to tackle the same.

Potential ameliorative effect of dietary quercetin against lead-induced oxidative stress, biochemical changes, and apoptosis in laying Japanese quails

Lead (Pb) is a widespread environmental pollutant which is a toxic threat to human and animal health. The present study was designed to evaluate the ameliorative role of quercetin in laying quails exposed to Pb. A total of 112 birds were randomly divided into four groups. The control group was fed with basal diet, the Pb group was fed with ration supplemented with Pb at the dose of 100 mg/kg (as Pb (II) acetate trihydrate), the Quercetin group was fed with ration supplemented with quercetin at the dose of 400 mg/kg, and the Pb+ Quercetin group was fed with ration supplemented with Pb at the dose of 100 mg/kg and quercetin at dose of 400 mg/kg. Results showed that serum total protein, glucose, albumin, and blood urea nitrogen (BUN) values of the Pb + Quercetin group partially improved with quercetin supplementation. Meanwhile, serum creatinine values of the Pb + Quercetin group was found to be significantly lower than that of the Pb group. Aspartate aminotransferase (AST) and alanine transaminase (ALT) enzyme activities in the Quercetin and Pb + Quercetin groups were similar to those of the Control group, unlike the Pb group. Moreover, alkaline phosphatase (ALP) enzyme activity of the Pb + Quercetin group significantly improved with the addition of quercetin. We also found that malondialdehyde (MDA) levels of the kidney, liver, and heart were significantly reduced by quercetin supplementation. The glutathione, catalase, and glutathione peroxidase activities of the kidney, liver, and heart tissue were increased by quercetin supplementation. These results were in line with the observed apoptotic markers. The expression of caspase-3 and caspase-9 were significantly decreased by quercetin supplementation. It may be concluded that dietary supplementation with quercetin ameliorates the toxic effects of Pb exposure by alleviating oxidative stress, biochemical changes, and apoptosis in quails.