Metals and apoptosis: recent developments

Microplastics at an environmentally relevant dose enhance mercury toxicity in a marine copepod under multigenerational exposure: Multi-omics perspective

Here, we subjected the marine copepod Tigriopus japonicus to environmentally-relevant concentrations of microplastics (MPs) and mercury (Hg) for three generations (F0-F2) to investigate their physiological and molecular responses. Hg accumulation and phenotypic traits were measured in each generation, with multi-omics analysis conducted in F2. The results showed that MPs insignificantly impacted the copepod's development and reproduction, however, which were significantly compromised by Hg exposure. Interestingly, MPs significantly increased Hg accumulation and consequently aggravated this metal toxicity in T. japonicus, demonstrating their carrier role. Multi-omics analysis indicated that Hg pollution produced numerous toxic events, e.g., induction of apoptosis, damage to cell/organ morphogenesis, and disordered energy metabolism, ultimately resulting in retarded development and decreased fecundity. Importantly, MPs enhanced Hg toxicity mainly via increased oxidative apoptosis, compromised cell/organ morphogenesis, and energy depletion. Additionally, phosphoproteomic analysis revealed extensive regulation of the above processes, and also impaired neuron activity under combined MPs and Hg exposure. These alterations adversely affected development and reproduction of T. japonicus. Overall, our findings should offer novel molecular insights into the response of T. japonicus to long-term exposure to MPs and Hg, with a particular emphasis on the carrier role of MPs on Hg toxicity.

Electrochemiluminescence assay for the impact of Ganoderma lucidum polysaccharides on resisting arsenic-induced apoptosis

Ganoderma lucidum (G. lucidum) is a traditional edible fungus with strong medicinal value. G. lucidum polysaccharides (GLP) encapsulate many of the key beneficial properties of this species, providing a valuable tool for the treatment of a range of diseases. The present study was developed to explore the protective benefits of GLP treatment in the context of arsenic poisoning. Through microscopy and flow cytometry experiments, NaAsO2 was found to induce rat tracheal epithelial (RTE) cell apoptosis, together with reductions in cell surface epidermal growth factor receptor (EGFR) expression. GLP treatment, however, was able to reduce apoptosis rates and elevate the expression of EGFR relative to NaAsO2-treated cells. GLP extracts (50, 100, 200 mg·mL-1) prepared from four types of G. lucidum were administered to RTE cells damaged with arsenic, revealing limited differences in position resistance among these varieties. This work provides reference for the pharmaceutical and medical research of G. lucidum.

An Overview of Hexavalent Chromium-Induced Necroptosis, Pyroptosis, and Ferroptosis

Heavy metals are common environmental industrial pollutants. Due to anthropogenic activity, chromium, especially its hexavalent form [Cr(VI)], is a widespread environmental contaminant that poses a threat to human health. In this review paper, we summarize the currently reported molecular mechanisms involved in chromium toxicity with a focus on the induction of pro-inflammatory non-apoptotic cell death pathways such as necroptosis, pyroptosis, and ferroptosis. The review highlights the ability of chromium to induce necroptosis, pyroptosis, and ferroptosis revealing the signaling pathways involved. Cr(VI) can induce RIPK1/RIPK3-dependent necroptosis both in vitro and in vivo. Chromium toxicity is associated with pyroptotic NLRP3 inflammasome/caspase-1/gasdermin D-dependent secretion of IL-1β and IL-18. Furthermore, this review emphasizes the role of redox imbalance and intracellular iron accumulation in Cr(VI)-induced ferroptosis. Of note, the crosstalk between the investigated lethal subroutines in chromium-induced toxicity is primarily mediated by reactive oxygen species (ROS), which are suggested to act as a rheostat determining the cell death pathway in cells exposed to chromium. The current study provides novel insights into the pro-inflammatory effects of chromium, since necroptosis, pyroptosis, and ferroptosis affect inflammation owing to their immunogenic properties linked primarily with damage-associated molecular patterns. Inhibition of these non-apoptotic lethal subroutines can be considered a therapeutic strategy to reduce the toxicity of heavy metals, including chromium.

Association of combined lead, cadmium, and mercury with systemic inflammation

Background

Exposure to environmental metals has been increasingly associated with systemic inflammation, which is implicated in the pathogenesis of various chronic diseases, including those with neurodegenerative aspects. However, the complexity of exposure and response relationships, particularly for mixtures of metals, has not been fully elucidated.

Objective

This study aims to assess the individual and combined effects of lead, cadmium, and mercury exposure on systemic inflammation as measured by C-reactive protein (CRP) levels, using data from the National Health and Nutrition Examination Survey (NHANES) 2017-2018.

Methods

We employed Bayesian Kernel Machine Regression (BKMR) to analyze the NHANES 2017-2018 data, allowing for the evaluation of non-linear exposure-response functions and interactions between metals. Posterior Inclusion Probabilities (PIP) were calculated to determine the significance of each metal's contribution to CRP levels.

Results

The PIP results highlighted mercury's significant contribution to CRP levels (PIP = 1.000), followed by cadmium (PIP = 0.6456) and lead (PIP = 0.3528). Group PIP values confirmed the importance of considering the metals as a collective group in relation to CRP levels. Our BKMR analysis revealed non-linear relationships between metal exposures and CRP levels. Univariate analysis showed a flat relationship between lead and CRP, with cadmium having a positive relationship. Mercury exhibited a U-shaped association, indicating both low and high exposures as potential risk factors for increased inflammation. Bivariate analysis confirmed this relationship when contaminants were combined with lead and cadmium. Analysis of single-variable effects suggested that cadmium and lead are associated with higher values of the h function, a flexible function that takes multiple metals and combines them in a way that captures the complex and potentially nonlinear relationship between the metals and CRP. The overall exposure effect of all metals on CRP revealed that exposures below the 50th percentile exposure level are associated with an increase in CRP levels, while exposures above the 60th percentile are linked to a decrease in CRP levels.

Conclusions

Our findings suggest that exposure to environmental metals, particularly mercury, is associated with systemic inflammation. These results highlight the need for public health strategies that address the cumulative effects of metal exposure and reinforce the importance of using advanced statistical methods to understand the health impact of environmental contaminants. Future research should focus on the mechanistic pathways of metal-induced inflammation and longitudinal studies to ascertain the long-term effects of these exposures.

Embryonic Zebrafish as a Model for Investigating the Interaction between Environmental Pollutants and Neurodegenerative Disorders

Environmental pollutants have been linked to neurotoxicity and are proposed to contribute to neurodegenerative disorders. The zebrafish model provides a high-throughput platform for large-scale chemical screening and toxicity assessment and is widely accepted as an important animal model for the investigation of neurodegenerative disorders. Although recent studies explore the roles of environmental pollutants in neurodegenerative disorders in zebrafish models, current knowledge of the mechanisms of environmentally induced neurodegenerative disorders is relatively complex and overlapping. This review primarily discusses utilizing embryonic zebrafish as the model to investigate environmental pollutants-related neurodegenerative disease. We also review current applicable approaches and important biomarkers to unravel the underlying mechanism of environmentally related neurodegenerative disorders. We found embryonic zebrafish to be a powerful tool that provides a platform for evaluating neurotoxicity triggered by environmentally relevant concentrations of neurotoxic compounds. Additionally, using variable approaches to assess neurotoxicity in the embryonic zebrafish allows researchers to have insights into the complex interaction between environmental pollutants and neurodegenerative disorders and, ultimately, an understanding of the underlying mechanisms related to environmental toxicants.

Multi-omic validation of the cuproptosis-sphingolipid metabolism network: modulating the immune landscape in osteosarcoma

Background

The current understanding of the mechanisms by which metal ion metabolism promotes the progression and drug resistance of osteosarcoma remains incomplete. This study aims to elucidate the key roles and mechanisms of genes involved in cuproptosis-related sphingolipid metabolism (cuproptosis-SPGs) in regulating the immune landscape, tumor metastasis, and drug resistance in osteosarcoma cells.

Methods

This study employed multi-omics approaches to assess the impact of cuproptosis-SPGs on the prognosis of osteosarcoma patients. Lasso regression analysis was utilized to construct a prognostic model, while multivariate regression analysis was applied to identify key core genes and generate risk coefficients for these genes, thereby calculating a risk score for each osteosarcoma patient. Patients were then stratified into high-risk and low-risk groups based on their risk scores. The ESTIMATE and CIBERSORT algorithms were used to analyze the level of immune cell infiltration within these risk groups to construct the immune landscape. Single-cell analysis was conducted to provide a more precise depiction of the expression patterns of cuproptosis-SPGs among immune cell subtypes. Finally, experiments on osteosarcoma cells were performed to validate the role of the cuproptosis-sphingolipid signaling network in regulating cell migration and apoptosis.

Results

In this study, seven cuproptosis-SPGs were identified and used to construct a prognostic model for osteosarcoma patients. In addition to predicting survival, the model also demonstrated reliability in forecasting the response to chemotherapy drugs. The results showed that a high cuproptosis-sphingolipid metabolism score was closely associated with reduced CD8 T cell infiltration and indicated poor prognosis in osteosarcoma patients. Cellular functional assays revealed that cuproptosis-SPGs regulated the LC3B/ERK signaling pathway, thereby triggering cell death and impairing migration capabilities in osteosarcoma cells.

Conclusion

The impact of cuproptosis-related sphingolipid metabolism on the survival and migration of osteosarcoma cells, as well as on CD8 T cell infiltration, highlights the potential of targeting copper ion metabolism as a promising strategy for osteosarcoma patients.

Metal Toxicity: Effects on Energy Metabolism in Fish

Metals are dispersed in natural environments, particularly in the aquatic environment, and accumulate, causing adverse effects on aquatic life. Moreover, chronic polymetallic water pollution is a common problem, and the biological effects of exposure to complex mixtures of metals are the most difficult to interpret. In this review, metal toxicity is examined with a focus on its impact on energy metabolism. Mechanisms regulating adenosine triphosphate (ATP) production and reactive oxygen species (ROS) emission are considered in their dual roles in the development of cytotoxicity and cytoprotection, and mitochondria may become target organelles of metal toxicity when the transmembrane potential is reduced below its phosphorylation level. One of the main consequences of metal toxicity is additional energy costs, and the metabolic load can lead to the disruption of oxidative metabolism and enhanced anaerobiosis.

What does scientometry tell us about mercury toxicology and its biological impairments?

Mercury is a toxic pollutant that poses risks to both human and environmental health, making it a pressing public health concern. This study aimed to summarize the knowledge on mercury toxicology and the biological impairments caused by exposure to mercury in experimental studies and/or diagnosis in humans. The research was conducted on the main collection of Web of Science, employing as a methodological tool a bibliometric analysis. The selected articles were analyzed, and extracted data such as publication year, journal, author, title, number of citations, corresponding author's country, keywords, and the knowledge mapping was performed about the type of study, chemical form of mercury, exposure period, origin of exposure, tissue/fluid of exposure measurement, mercury concentration, evaluation period (age), mercury effect, model experiments, dose, exposure pathway, and time of exposure. The selected articles were published between 1965 and 2021, with Clarkson TW being the most cited author who has also published the most articles. A total of 38% of the publications were from the USA. These studies assessed the prenatal and postnatal effects of mercury, emphasizing the impact of methylmercury on neurodevelopment, including motor and cognitive evaluations, the association between mercury and autism, and an evaluation of its protective effects against mercury toxicity. In observational studies, the blood, umbilical cord, and hair were the most frequently used for measuring mercury levels. Our data analysis reveals that mercury neurotoxicology has been extensively explored, but the association among the outcomes evaluated in experimental studies has yet to be strengthened. Providing metric evidence on what is unexplored allows for new studies that may help governmental and non-governmental organizations develop guidelines and policies.

Content of Toxic Elements (Arsenic, Cadmium, Mercury, Lead) in Eggs from an Ethically Managed Laying Hen Farm

Domestic chicken farming has been promoted and spread in several Italian municipalities and worldwide as an aid to the self-consumption of domestically produced food. This study investigated the levels of four toxic elements (As, Cd, Hg, and Pb) in eggs from an ethical laying hen farm, comparing the element concentrations with those possibly present in supermarket eggs. A total of 201 eggs, 141 from the farm and produced by different hen genotypes, and 60 from the supermarket, were collected. The levels of the toxic elements were evaluated in the yolk, albumen, and eggshells of all eggs. The results show that the supermarket eggs' yolk and albumen were more contaminated with lead, compared to the rural eggs. Contrarily, the mean content of arsenic was higher in the albumen and eggshells of the rural eggs, compared to the supermarket eggs. The cadmium content was below the LOQ (0.005 mg/kg) in all samples. The mercury content was below or around the LOQ in all rural eggs. Overall, the supermarket egg albumens were significantly more contaminated than the rural ones. No significant differences were found in quality parameters for both types of eggs. The toxic element values that were detected were in line with other studies in the literature. However, despite the concentrations found not representing a risk to the consumers' health, the results of this study raise a potential food safety issue, and it would be desirable to set specific MRLs for eggs for consumers' protection.

Curcumin protects against cadmium-induced germ cell death in the testis of rats

Introduction

Cadmium (Cd) has been shown to disrupt the reproductive system. In this study, we evaluated the protective effects of Curcumin (Cur) against Cd-induced reproductive toxicity.

Methods

Exploring the role of Cur in Cd-treated rat models.

Results

The study demonstrated that Cd treatment impaired the seminiferous epithelium, leading to increased apoptosis of germ cells. Interestingly, pretreatment with Cur ameliorated the histological damage and decreased the germ cell apoptosis induced by Cd. Furthermore, after Cd exposure, B-cell lymphoma-2 expression was significantly decreased while Bax expression was increased. Pretreatment of rats with Cur protected against germ cell apoptosis by improving the expression of B-cell lymphoma-2 and reducing Bax. Additionally, Cd treatment increased reactive oxygen species, resulting in a decrease in antioxidant enzymes. However, pretreatment of rats with Cur followed by Cd administration led to a substantial decrease in reactive oxygen species levels and increased activities of antioxidant enzymes. Ultrastructural investigations revealed that damage to the mitochondrial structure was significantly ameliorated by Cur pretreatment in Cd-treated rats. Notably, Cur significantly activated the peroxisome proliferator-activated receptor gamma coactivator 1a/Sirtuins-3 signaling pathway.

Conclusions

Overall, our data suggest that Cd induces germ cell apoptosis through mitochondrial-induced oxidative stress, but Cur pretreatment offers strong protection against Cd-induced reproductive toxicity.

The mechanism of nickel-induced autophagy and its role in nephrotoxicity

Nickel (Ni), an environmental health hazard, is nephrotoxic to humans, but the exact mechanism is unknown. This study aims to identify whether nephrotoxicity is associated with autophagy. Here, nickel chloride (NiCl2) increased autophagy in TCMK-1 cells. NiCl2 induces autophagy through Akt and AMPK/mTOR pathways. Next, oxidative stress was investigated in NiCl2-induced autophagy. The findings demonstrated that the antioxidant (NAC) or mitochondrial targeted antioxidant (Mito-TEMPO) attenuated NiCl2-induced autophagy, reversed the influence on AMPK-mTOR and Akt pathways. Additionally, our study examined the role of autophagy in NiCl2-induced nephrotoxicity. Autophagy inhibition with 3-MA could inhibit cell viability and increase apoptosis in the TCMK-1 cells, however, autophagy promotion with rapamycin relieved cytotoxicity and decreased apoptosis. Additionally, co-treatment with Z-VAD-FMK reduced cytotoxicity, but did not affect autophagy. Besides, NiCl2 can increase the level of mitophagy in vivo and vitro. Mitophagy inhibition could inhibit cell viability and increase apoptosis in the TCMK-1 cells, whereas, promotion of mitophagy could increase cell viability and decrease apoptosis. In summary, above-mentioned results showed that NiCl2 induces autophagy in TCMK-1 cells through oxidative stress-dependent AMPK/AKT-mTOR pathway, autophagy plays a role in reducing NiCl2-induced renal toxicity, and a major mechanism in autophagy's inhibitory effect on NiCl2-induced apoptosis may be mitophagy.

Nanoenabled Intracellular Metal Ion Homeostasis Regulation for Tumor Therapy

Endogenous essential metal ions play an important role in many life processes, especially in tumor development and immune response. The approval of various metallodrugs for tumor therapy brings more attention to the antitumor effect of metal ions. With the deepening understanding of the regulation mechanisms of metal ion homeostasis in vivo, breaking intracellular metal ion homeostasis becomes a new means to inhibit the proliferation of tumor cells and activate antitumor immune response. Diverse nanomedicines with the loading of small molecular ion regulators or metal ions have been developed to disrupt metal ion homeostasis in tumor cells, with higher safety and efficiency than free small molecular ion regulators or metal compounds. This comprehensive review focuses on the latest progress of various intracellular metal ion homeostasis regulation-based nanomedicines in tumor therapy including calcium ion (Ca2+ ), ferrous ion (Fe2+ ), cuprous ion (Cu+ ), managanese ion (Mn2+ ), and zinc ion (Zn2+ ). The physiological functions and homeostasis regulation processes of ions are summarized to guide the design of metal ion regulation-based nanomedicines. Then the antitumor mechanisms of various ions-based nanomedicines and some efficient synergistic therapies are highlighted. Finally, the challenges and future developments of ion regulation-based antitumor therapy are also discussed, hoping to provide a reference for finding more effective metal ions and synergistic therapies.

Rutin, Puerarin and Silymarin Regulated Aluminum-Induced Imbalance of Neurotransmitters and Metal Elements in Brain of Rats

Non-specifically binding of aluminum to various substances in the organism can result in toxicity. The accumulation of large amounts of aluminum can cause an imbalance in metal homeostasis and interfere with the synthesis and release of neurotransmitters. Flavonoids have strong metal chelating activity, which can reduce damage to the central nervous system. The purpose of this study was to investigate the protective effect of three representative flavonoids, rutin, puerarin and silymarin, on the brain toxicity induced by long-term exposure to aluminum trichloride (AlCl3). Sixty-four Wistar rats were randomly divided into eight groups (n = 8). The rats in six intervention groups were given 100 or 200 mg/kg BW/day of three different flavonoids for four weeks after a 4-week exposure to 281.40 mg/kg BW/day AlCl3·6H2O, while the rats in the AlCl3-toxicity and control groups were given the vehicle after the period of AlCl3 exposure. The results showed that rutin, puerarin, and silymarin could increase the concentrations of magnesium, iron, and zinc in the brains of the rats. Moreover, the intake of these three flavonoids regulated the homeostasis of amino acid neurotransmitters and adjusted the concentrations of monoamine neurotransmitters to normal levels. Taken together, our data suggest that rutin, puerarin, and silymarin could ameliorate AlCl3-induced brain toxicity in the rats by regulating imbalance of metal elements and neurotransmitters in the brains of rats.

Cadmium as an ovarian toxicant: A review

Cadmium (Cd) is a ubiquitous heavy metal toxicant with no biological function in the human body. Considerably, because of its long biological half-life and very low excretion rate, Cd is inclined to accumulate and cause deleterious effects on various body organs (e.g., liver, kidney, and ovary) in humans and animals. Ovaries are the most vulnerable targets of Cd toxicity. Cd has been shown to induce oxidative stress, follicular atresia, hormonal imbalance, and impairment of oocyte growth and development. Moreover, Cd toxicity has been associated with increasing incidences of menstrual disorders, pregnancy loss, preterm births, delayed puberty, and female infertility. Therefore, it is crucial to understand how Cd poisoning impacts specific ovarian processes for the development of preventive interventions to enhance female fertility. The current review attempts to collate the recent findings on Cd-induced oxidative stress, follicular apoptosis, steroid synthesis inhibition, and teratogenic toxicity, along with their possible mechanisms in the ovarian tissue of different animal species. Additionally, the review also summarizes the studies related to the use of many antioxidants, medicinal herbs, and other compounds as remedial approaches for managing Cd-induced ovarian toxicity.

Targeting Autophagy, Apoptosis, and Oxidative Perturbations with Dapagliflozin Mitigates Cadmium-Induced Cognitive Dysfunction in Rats

Cognitive decline and Alzheimer-like neuropathology are common manifestations of cadmium toxicity. Thanks to its antioxidant/anti-apoptotic features, dapagliflozin has demonstrated promising neuroprotective actions. However, its effect on cadmium-induced neurotoxicity is lacking. The present work aimed to examine whether dapagliflozin could protect rats from cadmium-evoked cognitive decline. In this study, the behavioral disturbances and hippocampal biomolecular alterations were studied after receiving dapagliflozin. Herein, cadmium-induced memory/learning decline was rescued in the Morris water maze, novel object recognition task, and Y-shaped maze by dapagliflozin. Meanwhile, the hippocampal histopathological abnormalities were mitigated. The molecular mechanisms revealed that dapagliflozin lowered hippocampal expression of p-tau and Aβ42 neurotoxic proteins while augmenting acetylcholine. The cognitive enhancement was triggered by hippocampal autophagy stimulation, as indicated by decreased SQSTM-1/p62 and Beclin 1 upregulation. Meanwhile, a decrease in p-mTOR/total mTOR and an increase in p-AMPK/total AMPK ratio were observed in response to dapagliflozin, reflecting AMPK/mTOR cascade stimulation. Dapagliflozin, on the other hand, dampened the pro-apoptotic processes in the hippocampus by downregulating Bax, upregulating Bcl-2, and inactivating GSK-3β. The hippocampal oxidative insult was mitigated by dapagliflozin as seen by lipid peroxide lowering, antioxidants augmentation, and SIRT1/Nrf2/HO-1 pathway activation. In conclusion, dapagliflozin's promising neuroprotection was triggered by its pro-autophagic, anti-apoptotic, and antioxidant properties.

Combined Effects of Fluoride and Arsenic on Mitochondrial Function in the Liver of Rat

Biochemical and/or molecular mechanisms of arsenic or fluoride toxicity in experimental animals have been widely investigated in the recent past. However, their combined effects on target cells/organelle are poorly understood. The present study was executed to delineate their combined effects on mitochondrial function in the liver of rat. Female Wistar rats (140 ± 20 g) were force fed individually or in combination with sodium arsenate (4 mg/kg body weight) and sodium fluoride (4 mg/kg body weight) for 90 days. Thereafter, established markers of mitochondrial function viz. mitochondrial lipid peroxidation, oxidative phosphorylation, ATPase, succinic dehydrogenase, and caspase-3 activity were determined. Cytochrome C release and oxidative DNA damage were also estimated in the liver of respective groups of rats. The study showed significant differences in these results amongst the three groups. Observations on parameters viz. LPO, cytochrome-C, caspase-3, and 8-OHdG suggested an antagonistic relationship between these two elements. Results on ATPase, SDH, and ADP:O ratio indicated synergism. It is concluded that AsIII + F in combination may express differential effects on signalling pathways and proapoptotic/antiapoptotic proteins/genes that contribute to liver cell death. Interaction of As and F with mitochondria.

A review on chromium health hazards and molecular mechanism of chromium bioremediation

Living beings have been devastated by environmental pollution, which has reached its peak. The disastrous pollution of the environment is in large part due to industrial wastes containing toxic pollutants. The widespread use of chromium (Cr (III)/Cr (VI)) in industries, especially tanneries, makes it one of the most dangerous environmental pollutants. Chromium pollution is widespread due to ineffective treatment methods. Bioremediation of chromium (Cr) using bacteria is very thoughtful due to its eco-friendly and cost-effective outcome. In order to counter chromium toxicity, bacteria have numerous mechanisms, such as the ability to absorb, reduce, efflux, or accumulate the metal. In this review article, we focused on chromium toxicity on human and environmental health as well as its bioremediation mechanism.

Genotoxicity and mutagenicity in blood and drinking water induced by arsenic in an impacted gold mining region in Colombia

Arsenic (As) is one of the most dangerous substances that can affect human health and long-term exposure to As in drinking water can even cause cancer. The objective of this study was to investigate the concentrations of total As in the blood of inhabitants of a Colombian region impacted by gold mining and to evaluate its genotoxic effect through DNA damage by means of the comet assay. Additionally, the concentration of As in the water consumed by the population as well as the mutagenic activity of drinking water (n = 34) in individuals were determined by hydride generator atomic absorption spectrometry and the Ames test, respectively. In the monitoring, the study population was made up of a group of 112 people, including inhabitants of four municipalities: Guaranda, Sucre, Majagual, and San Marcos from the Mojana region as the exposed group, and Montería as a control group. The results showed DNA damage related to the presence of As in blood (p < 0.05) in the exposed population, and blood As concentrations were above the maximum allowable limit of 1 μg/L established by the ATSDR. A mutagenic activity of the drinking water was observed, and regarding the concentrations of As in water, only one sample exceeded the maximum permissible value of 10 μg/L established by the WHO. The intake of water and/or food containing As is potentially generating DNA damage in the inhabitants of the Mojana region, which requires surveillance and control by health entities to mitigate these effects.

Targeting Autophagy, Apoptosis, and SIRT1/Nrf2 Axis with Topiramate Underlies Its Neuroprotective Effect against Cadmium-Evoked Cognitive Deficits in Rats

Cadmium is an environmental toxicant that instigates cognitive deficits with excessive glutamate excitatory neuroactivity in the brain. Topiramate, a glutamate receptor antagonist, has displayed favorable neuroprotection against epilepsy, cerebral ischemia, and Huntington's disease; however, its effect on cadmium neurotoxicity remains to be investigated. In this study, topiramate was tested for its potential to combat the cognitive deficits induced by cadmium in rats with an emphasis on hippocampal oxidative insult, apoptosis, and autophagy. After topiramate intake (50 mg/kg/day; p.o.) for 8 weeks, behavioral disturbances and molecular changes in the hippocampal area were explored. Herein, Morris water maze, Y-maze, and novel object recognition test revealed that topiramate rescued cadmium-induced memory/learning deficits. Moreover, topiramate significantly lowered hippocampal histopathological damage scores. Mechanistically, topiramate significantly replenished hippocampal GLP-1 and dampened Aβ42 and p-tau neurotoxic cues. Notably, it significantly diminished hippocampal glutamate content and enhanced acetylcholine and GABA neurotransmitters. The behavioral recovery was prompted by hippocampal suppression of the pro-oxidant events with notable activation of SIRT1/Nrf2/HO-1 axis. Moreover, topiramate inactivated GSK-3β and dampened the hippocampal apoptotic changes. In tandem, stimulation of hippocampal pro-autophagy events, including Beclin 1 upregulation, was triggered by topiramate that also activated AMPK/mTOR pathway. Together, the pro-autophagic, antioxidant, and anti-apoptotic features of topiramate contributed to its neuroprotective properties in rats intoxicated with cadmium. Therefore, it may be useful to mitigate cadmium-induced cognitive deficits.

Copper-instigated modulatory cell mortality mechanisms and progress in oncological treatment investigations

Copper, a transition metal, serves as an essential co-factor in numerous enzymatic active sites and constitutes a vital trace element in the human body, participating in crucial life-sustaining activities such as energy metabolism, antioxidation, coagulation, neurotransmitter synthesis, iron metabolism, and tetramer deposition. Maintaining the equilibrium of copper ions within biological systems is of paramount importance in the prevention of atherosclerosis and associated cardiovascular diseases. Copper induces cellular demise through diverse mechanisms, encompassing reactive oxygen species responses, apoptosis, necrosis, pyroptosis, and mitochondrial dysfunction. Recent research has identified and dubbed a novel regulatory cell death modality-"cuprotosis"-wherein copper ions bind to acylated proteins in the tricarboxylic acid cycle of mitochondrial respiration, resulting in protein aggregation, subsequent downregulation of iron-sulfur cluster protein expression, induction of proteotoxic stress, and eventual cell death. Scholars have synthesized copper complexes by combining copper ions with various ligands, exploring their significance and applications in cancer therapy. This review comprehensively examines the multiple pathways of copper metabolism, copper-induced regulatory cell death, and the current status of copper complexes in cancer treatment.

Neuroprotective Impact of Linagliptin against Cadmium-Induced Cognitive Impairment and Neuropathological Aberrations: Targeting SIRT1/Nrf2 Axis, Apoptosis, and Autophagy

Cadmium is an environmental contaminant associated with marked neurotoxicity and cognitive impairment. Linagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, has demonstrated promising neuroprotection against cerebral ischemia and diabetic dementia. However, there has been no study of its effect on cadmium-induced cognitive deficits. In the present work, linagliptin's prospective neuroprotective effects against cadmium-evoked cognitive decline were examined in vivo in rats. The molecular pathways related to oxidative stress, apoptosis, and autophagy were investigated. Histology, immunohistochemistry, ELISA, and biochemical assays were performed on brain hippocampi after receiving linagliptin (5 mg/kg/day). The current findings revealed that cadmium-induced learning and memory impairment were improved by linagliptin as seen in the Morris water maze, Y-maze, and novel object recognition test. Moreover, linagliptin lowered hippocampal neurodegeneration as seen in histopathology. At the molecular level, linagliptin curtailed hippocampal DPP-4 and augmented GLP-1 levels, triggering dampening of the hippocampal neurotoxic signals Aβ42 and p-tau in rats. Meanwhile, it enhanced hippocampal acetylcholine and GABA and diminished the glutamate spike. The behavioral recovery was associated with dampening of the hippocampal pro-oxidant response alongside SIRT1/Nrf2/HO-1 axis stimulation. Meanwhile, linagliptin counteracted hippocampal apoptosis markers and inhibited the pro-apoptotic kinase GSK-3β. In tandem, linagliptin activated hippocampal autophagy by lowering SQSTM-1/p62 accumulation, upregulating Beclin 1, and stimulating AMPK/mTOR pathway. In conclusion, linagliptin's antioxidant, antiapoptotic, and pro-autophagic properties advocated its promising neuroprotective impact. Thus, linagliptin may serve as a management approach against cadmium-induced cognitive deficits.

Mass Spectrometry Detects Sphingolipid Metabolites for Discovery of New Strategy for Cancer Therapy from the Aspect of Programmed Cell Death

Sphingolipids, a type of bioactive lipid, play crucial roles within cells, serving as integral components of membranes and exhibiting strong signaling properties that have potential therapeutic implications in anti-cancer treatments. However, due to the diverse group of lipids and intricate mechanisms, sphingolipids still face challenges in enhancing the efficacy of different therapy approaches. In recent decades, mass spectrometry has made significant advancements in uncovering sphingolipid biomarkers and elucidating their impact on cancer development, progression, and resistance. Primary sphingolipids, such as ceramide and sphingosine-1-phosphate, exhibit contrasting roles in regulating cancer cell death and survival. The evasion of cell death is a characteristic hallmark of cancer cells, leading to treatment failure and a poor prognosis. The escape initiates with long-established apoptosis and extends to other programmed cell death (PCD) forms when patients experience chemotherapy, radiotherapy, and/or immunotherapy. Gradually, supportive evidence has uncovered the fundamental molecular mechanisms underlying various forms of PCD leading to the development of innovative molecular, genetic, and pharmacological tools that specifically target sphingolipid signaling nodes. In this study, we provide a comprehensive overview of the sphingolipid biomarkers revealed through mass spectrometry in recent decades, as well as an in-depth analysis of the six main forms of PCD (apoptosis, autophagy, pyroptosis, necroptosis, ferroptosis, and cuproptosis) in aspects of tumorigenesis, metastasis, and tumor response to treatments. We review the corresponding small-molecule compounds associated with these processes and their potential implications in cancer therapy.

More Effective Mobilization of Hg2+ from Human Serum Albumin Compared to Cd2+ by L-Cysteine at Near-Physiological Conditions

Although chronic low-level exposure to Hg²⁺ and Cd²⁺ causes human nephrotoxicity, the bioinorganic processes that deliver them to their target organs are poorly understood. Since the plasma protein human serum albumin (HSA) has distinct binding sites for these metal ions, we wanted to gain insight into these translocation processes and have employed size-exclusion chromatography coupled on-line to an inductively coupled plasma atomic emission spectrometer using phosphate-buffered saline mobile phases. When HSA 'labeled' with Hg²⁺ and Cd²⁺ (1:0.1:0.1) using 300 μM of L-methionine was analyzed, the co-elution of a single C, S, Cd, and Hg peak was observed, which implied the intact bis-metalated HSA complex. Since human plasma contains small molecular weight thiols and sulfur-containing metabolites, we analyzed the bis-metalated HSA complex with mobile phases containing 50-200 µM of L-cysteine (Cys), D,L-homocysteine (hCys), or glutathione (GSH), which provided insight into the comparative mobilization of each metal from their respective binding sites on HSA. Interestingly, 50 µM Cys, hCys, or GSH mobilized Hg²⁺ from its HSA binding site but only partially mobilized Cd²⁺ from its binding site. Since these findings were obtained at conditions simulating near-physiological conditions of plasma, they provide a feasible explanation for the higher 'mobility' of Hg²⁺ and its concomitant interaction with mammalian target organs compared to Cd²⁺. Furthermore, 50 µM Cys resulted in the co-elution of similar-sized Hg and Cd species, which provides a biomolecular explanation for the nephrotoxicity of Hg²⁺ and Cd²⁺.

Metabolomics: a promising tool for deciphering metabolic impairment in heavy metal toxicities

Heavy metals are the metal compounds found in earth's crust and have densities higher than that of water. Common heavy metals include the lead, arsenic, mercury, cadmium, copper, manganese, chromium, nickel, and aluminum. Their environmental levels are consistently rising above the permissible limits and they are highly toxic as enter living systems via inhalation, ingestion, or inoculation. Prolonged exposures cause the disruption of metabolism, altered gene and/or protein expression, and dysregulated metabolite profiles. Metabolomics is a state of the art analytical tool widely used for pathomolecular inv22estigations, biomarkers, drug discovery and validation of biotransformation pathways in the fields of biomedicine, nutrition, agriculture, and industry. Here, we overview studies using metabolomics as a dynamic tool to decipher the mechanisms of metabolic impairment related to heavy metal toxicities caused by the environmental or experimental exposures in different living systems. These investigations highlight the key role of metabolomics in identifying perturbations in pathways of lipid and amino acid metabolism, with a critical role of oxidative stress in metabolic impairment. We present the conclusions with future perspectives on metabolomics applications in meeting emerging needs.

Usnea Acid-Incorporated Ca2+ /Mn2+ Ions Reservoirs for Elevated Ion-Interference Therapy through Synergetic Biocatalysis and Osmolarity Imbalance

Ion-interference therapy (IIT) utilizes ions to disturb intracellular biological processes and has been received increasing attention in tumor treatments recently. However, the low therapeutic efficiency still hinders its further biological applications. Herein, via a simple and one-pot gas diffusion process, polyethylene glycol (PEG)-modified Mn2+ ions and usnic acid (UA)-incorporated CaCO3 nanomaterials (PEG CaMnUA) as Ca2+ /Mn2+ ions reservoirs are prepared for magnetic resonance imaging (MRI)-guided UA-elevated IIT. Among PEG CaMnUA, UA not only increases cytoplasmic Ca2+ ions to amplify Ca2+ overload caused by CaCO3 decomposition, but also enhances Mn2+ ions-participated Fenton-like biocatalysis by intracellular H2 O2 generation and glutathione consumption. Then increasing the intracellular oxidative stress and decreasing the triphosadenine supply induce apoptosis together, resulting in UA-boosted IIT. The simple and efficient design of the dual ions reservoirs will contribute to improve the antitumor activity of IIT and further development of calcium-based nanomaterials in the future.

The toxic metal hypothesis for neurological disorders

Multiple sclerosis and the major sporadic neurogenerative disorders, amyotrophic lateral sclerosis, Parkinson disease, and Alzheimer disease are considered to have both genetic and environmental components. Advances have been made in finding genetic predispositions to these disorders, but it has been difficult to pin down environmental agents that trigger them. Environmental toxic metals have been implicated in neurological disorders, since human exposure to toxic metals is common from anthropogenic and natural sources, and toxic metals have damaging properties that are suspected to underlie many of these disorders. Questions remain, however, as to how toxic metals enter the nervous system, if one or combinations of metals are sufficient to precipitate disease, and how toxic metal exposure results in different patterns of neuronal and white matter loss. The hypothesis presented here is that damage to selective locus ceruleus neurons from toxic metals causes dysfunction of the blood-brain barrier. This allows circulating toxicants to enter astrocytes, from where they are transferred to, and damage, oligodendrocytes, and neurons. The type of neurological disorder that arises depends on (i) which locus ceruleus neurons are damaged, (ii) genetic variants that give rise to susceptibility to toxic metal uptake, cytotoxicity, or clearance, (iii) the age, frequency, and duration of toxicant exposure, and (iv) the uptake of various mixtures of toxic metals. Evidence supporting this hypothesis is presented, concentrating on studies that have examined the distribution of toxic metals in the human nervous system. Clinicopathological features shared between neurological disorders are listed that can be linked to toxic metals. Details are provided on how the hypothesis applies to multiple sclerosis and the major neurodegenerative disorders. Further avenues to explore the toxic metal hypothesis for neurological disorders are suggested. In conclusion, environmental toxic metals may play a part in several common neurological disorders. While further evidence to support this hypothesis is needed, to protect the nervous system it would be prudent to take steps to reduce environmental toxic metal pollution from industrial, mining, and manufacturing sources, and from the burning of fossil fuels.

Dual-infinite coordination polymer-engineered nanomedicines for dual-ion interference-mediated oxidative stress-dependent tumor suppression

Recently, nanomedicine design has shifted from simple nanocarriers to nanodrugs with intrinsic antineoplastic activities for therapeutic performance optimization. In this regard, degradable nanomedicines containing functional inorganic ions have blazed a highly efficient and relatively safe ion interference paradigm for cancer theranostics. Herein, given the potential superiorities of infinite coordination polymers (ICPs) in degradation peculiarity and functional integration, a state-of-the-art dual-ICP-engineered nanomedicine is elaborately fabricated via integrating ferrocene (Fc) ICPs and calcium-tannic acid (Ca-TA) ICPs. Thereinto, Fc ICPs, and Ca-TA ICPs respectively serve as suppliers of ferrous iron ions (Fe²⁺) and calcium ions (Ca²⁺). After the acid-responsive degradation of ICPs, released TA from Ca-TA ICPs facilitated the conversion of released ferric iron (Fe³⁺) from Fc ICPs into highly active Fe²⁺. Owing to the dual-path oxidative stress and neighboring effect mediated by Fe²⁺ and Ca²⁺, such a dual-ICP-engineered nanomedicine effectively induces dual-ion interference against triple-negative breast cancer (TNBC). Therefore, this work provides a novel antineoplastic attempt to establish ICP-engineered nanomedicines and implement ion interference-mediated synergistic therapy.

Effects of N-Acetylcysteine Supplementation on Oxidative Stress and Expression of Apoptosis-Related Genes in Testicular Tissue of Rats Exposed to Lead

BACKGROUND

Lead occupational exposure is now a main concern in the modern world. Lead is a non-biodegradable element with multi-devastating effects on different organs. Acute or chronic exposure to lead is reported to be one of the most important causes of infertility both in males and females basically by inducing oxidative stress and apoptosis.

OBJECTIVES

The current study scrutinized the mitigating effects of N-acetylcysteine (NAC) on lead toxicity, oxidative stress, and apoptotic/anti-apoptotic genes in the testis tissues of male rats.

METHODS

Rats were randomly divided into a control group (G1) and four study groups treated with single and continuous doses of lead with and without NAC administration. Malondialdehyde (MDA), total antioxidant capacity (TAC), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were analyzed as oxidative stress biomarkers and the expression of apoptosis-related genes was studied using RT-PCR.

RESULTS

Continuous exposure to lead caused a significant decrease in sperm count, motility, viability, and morphology (P < 0.001). Number of germinal cells, Leydig cells, spermatocytes, and the diameter of seminiferous tubule were significantly decreased (P < 0.001) in G3 group. Continuous exposure to lead significantly decreased TAC content, but increased the levels of MDA and 8-OHdG (P < 0.001). Administration of continuous dose of lead dramatically increased expression of Bax, Caspase-3, Caspase-8, Cytochrome-C, MMP2, and MMP9 genes in testicular tissue. NAC treatments not only improved morphological changes and sperm quality, but also enhanced antioxidant balance and modulated apoptosis process in testicular tissue of rats.

CONCLUSION

Lead exposure strongly motivated testicular cells towards apoptosis, caused an oxidant/antioxidant imbalance, and decreased sperm quality along with morphological changes in testis cells. NAC treatments was associated with protective effects on testicular tissue mainly by rebalancing of the antioxidants capacity, as well as downregulation of apoptosis-related genes.

Relation between blood levels of heavy metals and some markers of oxidative stress among boys with neuropathic bladder and posterior urethral valve

BACKGROUND

The status of heavy metals in children with lower urinary tract pathology that may harm the upper tract, e.g., neuropathic bladder and posterior urethral valve and its relationship with oxidative stress has not been adequately investigated. Therefore, the object of the current work was to evaluate the concentrations of copper, zinc, cadmium and lead and their relations with levels of catalase (CAT), malondialdehyde (MDA) and glutathione (GSH) in boys with neuropathic bladder and posterior urethral valve.

METHODS

Thirty-six children with neuropathic bladder, 35 children with posterior urethral valve and 33 health controls were included in the study. In addition to routine laboratory tests, blood samples were collected from patients and controls to assess levels of Cu, Zn, Cd and Pb in addition to plasma concentrations of CAT, MDA and GSH.

RESULTS

Significantly elevated levels of Cu, Pb, CAT, MDA and GSH and significantly lower concentration of blood Zn were found in the studied groups compared to the controls. In the posterior urethral valve group, blood level of Cu was positively correlated with GSH while a significantly negative relation was observed between blood Zn and CAT activity among the neuropathic bladder patients.

CONCLUSION

Neuropathic bladder and posterior urethral valve may lead to abnormalities in the blood levels of heavy metals (i.e. Cu, Pb and Zn) and markers of oxidative stress (CAT, MDA and GSH). Therefore, the levels of theses metal ions should be monitored during the treatment course of neuropathic bladder and posterior urethral valve patients to prevent or minimize long-term oxidative injury.

Association of Blood Mercury Level with Liver Enzymes in Korean Adults: An Analysis of 2015-2017 Korean National Environmental Health Survey

Increased liver enzymes as a result of exposure to mercury and their toxic effects are not well understood in Korea at the population level. The effect of blood mercury concentration on alanine aminotransferase (ALT) and aspartate aminotransferase (AST) was evaluated after adjusting for sex, age, obesity, alcohol consumption habit, smoking, and exercise parameters in 3712 adults. The risk of abnormal liver function was measured using a multiple logistic regression analysis. Blood mercury concentration was divided into quartiles, and liver enzyme levels were compared for each quartile. ALT and AST levels were 10-20% higher in the second, third, and fourth quartiles compared to the first quartile. The risk of liver dysfunction or elevated liver enzymes was significantly higher in the second, third, and fourth quartiles than in the first quartile. As blood mercury levels increased, liver enzymes and mercury-induced hepatotoxicity increased. The increase in liver enzymes caused by mercury was more pronounced in the low-mercury concentration range. To reduce the long-standing problem of abnormal liver enzymes and liver function in Korea and other similar settings, it is important to decrease exposure to mercury through effective implementation of specific health and environmental strategies.

Health risk assessment of mercury in Nile tilapia (Oreochromis niloticus) fed housefly maggots

The bioaccumulation of total mercury (THg) and methylmercury (MeHg) by housefly maggots (HM) during the conversion of food waste (vegetables and meat (VM) and rice waste) under various waste feed ratios were investigated. Subsequently, Nile tilapia (Oreochromis niloticus) were fed with the commercial feed, commercial dried HM, dried HM, and fresh HM, followed by a human health risk assessment of Hg via fish consumption. The THg concentrations of HM fed with food waste ranged from 39.5 to 100 μg kg^-1 ww. Concentrations of MeHg in the maggots fed with 100 % vegetables and meat (VM) waste (13.7 ± 1.12 μg kg^-1 ww) was significantly higher than that fed with other mixed ratios of rice waste and VM waste (p<0.05). Concentrations of MeHg were positively correlated with the weight and lipid content of houseflies (p<0.05). THg and MeHg concentrations in tilapia fed with the converted HM (dried and fresh HM) were 22.5 ± 6.50 μg kg^-1 ww and 2.43 ± 0.36 μg kg^-1 ww, respectively. There was no significant difference in MeHg between tilapia fed the four experiment diets (p>0.05). Health risk assessment results indicated that mercury in tilapia fed the food waste-grown HM did not pose potential health risks to humans (target hazard quotient < 1). In conclusion, HM could convert food waste into high-quality and safe fish feeds for cultivating tilapia.

Nanomedicine-Enabled/Augmented Cell Pyroptosis for Efficient Tumor Nanotherapy

The terrible morbidity and mortality of malignant tumors urgently require innovative therapeutics, especially for apoptosis-resistant tumors. Pyroptosis, a pro-inflammatory form of programmed cell death (PCD), is featured with pore formation in plasma membrane, cell swelling with giant bubbles, and leakage of cytoplasmic pro-inflammatory cytokines, which can remodel the tumor immune microenvironment by stimulating a "cold" tumor microenvironment to be an immunogenic "hot" tumor microenvironment, and consequently augment the therapeutic efficiency of malignant tumors. Benefiting from current advances in nanotechnology, nanomedicine is extensively applied to potentiate, enable, and augment pyroptosis for enhancing cancer-therapeutic efficacy and specificity. This review provides a concentrated summary and discussion of the most recent progress achieved in this emerging field, highlighting the nanomedicine-enabled/augmented specific pyroptosis strategy for favoring the construction of next-generation nanomedicines to efficiently induce PCD. It is highly expected that the further clinical translation of nanomedicine can be accelerated by inducing pyroptotic cell death based on bioactive nanomedicines.

Duckweed: a potential phytosensor for heavy metals

Globally, heavy metal (HM) contamination is one of the primary causes of environmental pollution leading to decreased quality of life for those affected. In particular, HM contamination in groundwater poses a serious risk to human health and the potential for destabilization of aquatic ecosystems. At present, strategies to remove HM contamination from wastewater are inefficient, costly, laborious, and often the removal poses as much risk to the environment as the initial contamination. Phytoremediation, plant-based removal of contaminants from soil or water, has long been viewed as an economical and sustainable solution to remove toxic metals from the environment. However, to date, phytoremediation has demonstrated limited successes despite a large volume of literature supporting its potential. A key aspect for achieving robust and meaningful phytoremediation is the selection of a plant species that is well suited to the task. For the removal of pollutants from wastewater, hydrophytes, like duckweed, exhibit significant potential due to their rapid growth on nutrient-rich water, ease of collection, and ability to survive in various ecosystems. As a model for ecotoxicity studies, duckweed is an ideal candidate, as it is easy to cultivate under controlled and even sterile conditions, and the rapid growth enables multi-generational studies. Similarly, recent advances in the genetic engineering and genome-editing of duckweed will enable the transition from fundamental ecotoxicity studies to engineered solutions for phytoremediation of HMs. This review will provide insight into the suitability of duckweeds for phytoremediation of HMs and strategies for engineering next-generation duckweed to provide real-world environmental solutions.

Effect of the Graphene- Ni/NiFe2O4 Composite on Bacterial Inhibition Mediated by Protein Degradation

Recent investigations have demonstrated that nickel ferrite nanoparticles and their derivatives have toxicity effects on bacterial cells. In this study, we have prepared nickel ferrite nanoparticles (Ni/NiFe₂O₄) and nickel/nickel ferrite graphene oxide (Ni/NiFe₂O₄-GO) nanocomposite and evaluated their toxic effects on E. coli cells ATCC 25922. The prepared nanomaterials were characterized using X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and vibrating sample magnetometry techniques. The toxicity was evaluated using variations in cell viability, cell morphology, protein degradation, and oxidative stress. Ni/NiFe₂O₄-GO nanocomposites likewise prompt oxidative stress proved by the age of reactive oxygen species (ROS) and exhaustion of antioxidant glutathione. This is the first report indicating that Ni/NiFe₂O₄-GO nanocomposite-initiated cell death in E. coli through ROS age and oxidative stress.

Autophagy involvement in T lymphocyte signalling induced by nickel with quantitative phosphoproteomic analysis

Nickel-induced allergic contact dermatitis (ACD) is a common skin disease. The mechanism by which nickel causes ACD is not clear. There is no treatment for it, only symptomatic therapy. However, due to the lifetime sensitization characteristics, the recurrence rate in patients is high. T lymphocytes play a key role in nickel-induced ACD. Elucidating the potential mechanism underlying nickel-induced T lymphocyte signalling might make it possible to achieve targeted treatment of nickel-induced ACD. In our study, a phosphoproteomic approach based on tandem mass tag (TMT) labelling and LCMS/MS analyses was employed. An animal model of nickel allergy was established. Splenic T lymphocytes were purified for quantitative phosphoproteomic analysis. The numbers of phosphoproteins, phosphopeptides and phosphosites identified in this study were 3072, 7977 and 10,200, respectively. Comprehensive gene ontology (GO) analysis combined with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed that nickel can significantly affect the phosphorylation of the mTOR signalling pathway in T lymphocytes. Western blotting analysis was used to detect changes in the expression of autophagy-related proteins (Beclin 1, LC3II, and p62). Nickel allergy changed autophagy-related protein expression (p < 0.05). It has been demonstrated that nickel causes autophagy of T lymphocytes in the spleen. Using autophagy inhibitors to intervene, it was found that Th1 differentiation was inhibited, and the expression of Th1-related inflammatory factors was downregulated. Overall, the identification of relevant signalling pathways yielded new insights into the molecular mechanisms underlying nickel allergy and might help in the discovery and development of mechanism-based drugs.

Honokiol attenuate the arsenic trioxide-induced cardiotoxicity by reducing the myocardial apoptosis

Despite advantages of arsenic trioxide (ATO) in oncological practice, its clinical applications have been hampered by severe cardiotoxicity. The general mechanism of ATO-induced cardiotoxicity has been attributed to its damage to mitochondria, resulting in cardiac remodeling. Honokiol (HKL) is a naturally occurring compound derived from Magnolia bark. Previous studies have demonstrated that HKL exerts cardio-protective effects on ischemia/reperfusion (I/R) or chemical-induced cardiotoxicity by counteracting the toxic effects on mitochondria. The present study was conducted to investigate whether HKL pretreatment protects against ATO-induced cardiac oxidative damage and cell death. For the in vitro study, we evaluated the effects of ATO and/or Honokiol on reactive oxygen species (ROS) production and apoptosis induction in primary cultured cardiomyocytes; for the in vivo study, BALB/c mice were administrated with ATO and/or HKL for a period of 4 weeks, myocardial apoptosis, cardiac function, and cardiac remodeling (cardiac hypertrophy and cardiac fibrosis) were assessed at the end of administration. Our results demonstrated Honokiol pretreatment alleviated the ATO-induced boost in ROS concentration and the following apoptosis induction in primary cultured cardiomyocytes. In the mouse model, Honokiol pretreatment ameliorated ATO-induced myocardial apoptosis, cardiac dysfunction, and cardiac remodeling. Collectively, these results indicated that Honokiol provide a protection against ATO-induced cardiotoxicity by reducing mitochondrial damage. In addition, given that Honokiol has shown considerable suppressive effects on leukemia cells, our data also imply that ATO and Honokiol combination may possibly be a superior avenue in leukemia therapy.

Combined effects of polystyrene microplastics and copper on antioxidant capacity, immune response and intestinal microbiota of Nile tilapia (Oreochromis niloticus)

Microplastics (MPs) coexist with other pollutants (such as heavy metals) in water, adversely impacting aquatic organisms, which might cause unpredictable ecological risks. This study aims to evaluate the effect of copper (Cu²⁺) and polystyrene microplastics (PS-MPs) on antioxidant capacity, immune response and intestinal microbiota of Nile tilapia. Cu²⁺ and PS-MPs co-exposure enhanced Cu²⁺ bioaccumulation in the liver of fish compared with Cu²⁺-alone exposure. Fish exposed to PS-MPs and Cu²⁺ displayed histopathologic alterations in the liver, intestine and gill. Exposure at low concentrations of Cu²⁺ in the C0 and CP0 groups can improve antioxidant capacity and immune response, while oxidative damage and inflammation existed in the high concentration of Cu²⁺ groups. Intestinal microbiota results showed that the diversity and structure were changed by Cu²⁺ and PS-MPs exposure, and harmful bacterium even increased at high concentration of Cu²⁺ and PS-MPs exposure groups. All in all, PS-MPs aggravate the accumulation of Cu²⁺ and lead to perturbations in biological systems of Nile tilapia.

Protective Effect of Vitamin E on Cadmium-Induced Renal Oxidative Damage and Apoptosis in Rats

Cadmium (Cd), a widely distributed heavy metal, is extremely toxic to the kidney. Vitamin E (VE) is an important antioxidant in the body. It is known that VE exerts a protective effect on renal oxidative damage caused by Cd, but the effect and mechanism of VE on apoptosis are not fully understood. Thus, we conducted this study to explore the protective effect of VE on Cd-induced renal apoptosis and to elucidate its potential mechanism. Thirty-two 9-week-old male Sprague-Dawley rats were randomly divided into four groups, namely control, VE (100 mg/kg VE), Cd (5 mg/kg CdCl₂), and VE + Cd (100 mg/kg VE + 5 mg/kg CdCl₂), and received intragastric administration of Cd and/or VE for 4 weeks. The results showed that Cd exposure significantly reduced the weight of the body and kidney, elevated the accumulation of Cd in the kidney as well as the levels of BUN and Scr in serum, caused renal histological alterations, decreased the GSH and T-AOC contents and antioxidant enzyme (SOD, CAT, GSH-PX) activities, and increased renal MDA content. And the increased number of TUNEL-positive cells by Cd was accompanied by upregulated mRNA and protein expressions of apoptotic regulatory molecules (Bax, Caspase-3, GRP94, GRP78, Caspase-8) and downregulated Bcl-2 expressions. However, the combined treatment of Cd and VE could restore the above parameters to be close to those in the control rats. In conclusion, VE supplement could alleviate Cd-induced rat renal damage and oxidative stress through enhancing the antioxidant defense system and inhibiting apoptosis of renal cells.

Nickel chloride induces spermatogenesis disorder by testicular damage and hypothalamic-pituitary-testis axis disruption in mice

As a common environmental pollutant, nickel chloride (NiCl₂) poses serious threat to human and animals health. NiCl₂ has adverse effects on reproductive function in male, however, the underlying mechanisms are not fully illuminated. In this study, 64 male ICR mice were divided into four groups (8 mice per each period/ group), in which mice orally administrated with 0, 7.5, 15 or 30 mg/kg body weight for 14 or 28 consecutive days, respectively. The results showed that the sperm concentration (12.95%, 29.78% and 37.63% -) and sperm motility (19.79%, 34.88% and 43.10%) were dose-dependent significantly reduced, and the total sperm malformation rates (110.15%, 206.84% and 292.27%) were dose-dependent significantly elevated in the 7.5, 15 and 30 mg/kg NiCl₂ treatment groups (vs control at 28 days), respectively (P < 0.05). Meanwhile, NiCl₂ also decreased the relative weights of testis and epididymis and caused histopathological lesions of testis and epididymis. Furthermore, serum testosterone levels were significantly decreased after NiCl₂ treatment. And the findings showed that NiCl₂ down-regulated the expression of LH-R, StAR, P450scc, 3β-HSD, 17β-HSD, ABP and INHβB in the testis, however, the relative genes in the hypothalamus (Kiss-1, GPR54 and GnRH) and pituitary (GnRH-R, LHβ and FSHβ) did not exhibit noticeable change. In summary, NiCl₂ induced spermatogenesis disorder by testicular damage and hypothalamic-pituitary-testis axis disruption in mice, and only impaired the genes on the testis of HPT axis.

The role of microRNAs in regulating cadmium-induced apoptosis by targeting Bcl-2 in IEC-6 cells

Cadmium (Cd) is one of the most harmful environmental pollutants and has been found to have adverse effects on the gut. However, the toxic effects and potential mechanism of Cd on intestinal epithelial cells (IECs) are poorly understood. This study evaluated the effects of Cd exposure (0, 0.25, 0.5, 1, 2, and 4 μM) on IEC-6 cells in terms of cell viability and apoptosis, as well as apoptosis-associated gene expression. The results indicated that low doses (0.25- 1 μM) of Cd exhibited hormetic effects, while high doses of Cd (2 and 4 μM) reduced cell viability. The apoptotic effect increased in a dose-dependent pattern. Moreover, the mRNA levels of the Bcl-2, Bax and Caspase 3 genes were altered, which was in agreement with their protein expression. Based on sequencing analysis, the expression pattern of the microRNAs (miRNAs) changed significantly in the 2 μM Cd-treated group. QRT-PCR verified that 7 miRNAs, including miR-124-3p and miR-370-3p, were all upregulated with dose-effect relationship. Besides, transfection of miR-124-3p and miR-370-3p mimics /inhibitor and Bcl-2 siRNA into IEC-6 cells verified that these two miRNAs could regulate Cd-induced apoptosis by targeting Bcl-2. Finally, the direct targeting relationship between miR-370-3p and Bcl-2 gene was confirmed by luciferase reporter assay. Overall, the results demonstrated that Cd exposure could induce apoptosis in IEC-6 cells. The potential mechanism may be interference with the regulation of Bcl-2 gene expression by miR-370-3p and miR-124-3p.

Arsenic trioxide induces expression of BCL-2 expression via NF-κB and p38 MAPK signaling pathways in BEAS-2B cells during apoptosis

Inorganic arsenic compounds are environmental toxicants that are widely distributed in air, water, and food. B-cell lymphoma 2 (BCL-2) is an oncogene having anti-apoptotic function. In this study, we clarify that BCL-2, as a pro-apoptotic factor, participates in As₂O₃-induced apoptosis in BEAS-2B cells. Specifically, As₂O₃ stimulated the expression of BCL-2 mRNA and protein in a dose-dependent manner which was highly accumulated in the nucleus of BEAS-2B cell together with chromatin condensation and DNA fragmentation during apoptosis. Mechanistically, the process described above is mediated through the NF-κB and p38 MAPK signaling pathways, which can be abated by corresponding inhibitors, such as BAY11-7082 and SB203580, respectively. Additionally, BAY11-7082, actinomycin D, and cycloheximide have inhibitory effects on As₂O₃-induced expression of BCL-2 mRNA and protein, and restore the cell viability of BEAS-2B cells. Suppression of BCL-2 protein activation by ABT-199 also restored viability of BEAS-2B cell in As₂O₃-induced apoptosis. Furthermore, As₂O₃ increased the level of BCL-2 phosphorylation. These results suggest that in BEAS-2B cells, As₂O₃-induced apoptosis is mainly dominated by BCL-2 upregulation, nuclear localization and phosphorylation. The study presented here provides a novel insight into the molecular mechanism of BCL-2-induced apoptosis.

A pH-targeted and NIR-responsive NaCl-nanocarrier for photothermal therapy and ion-interference therapy

Transport ions into cells through nanocarrier to achieve ion-interference therapy provides new inspiration for cancer treatment. In this work, a pH-targeted and NIR-responsive NaCl-nanocarrier is prepared using surfactant Vitamin E-O(EG₂-Glu) and modified with polydopamine (PDA) and pH-sensitive zwitterionic chitosan (ZWC). The NaCl-nanocarrier is decorated with NH₄HCO₃ and IR-780 to introduce near-infrared (NIR)-responsive performance and imaging. Once the NaCl-nanocarrier is exposed to NIR laser, the temperature rises rapidly because of the excellent photothermal conversion ability of PDA, then NH₄HCO₃ is decomposed into NH₃ and CO₂, which burst the nanocarrier, resulting in Cl^- and Na⁺ "bomb-like" release. This pH-targeted nanocarrier accumulates more at tumor site and when irradiating the site with NIR light, the temperature rises and excessive Cl^- and Na⁺ are released to destroy the ion homeostasis and inhibit tumor growth effectively. Through this strategy, the unique combination of ion interference therapy and photothermal therapy is achieved.

Autism spectrum disorder: Trace elements imbalances and the pathogenesis and severity of autistic symptoms

The identification of biomarkers as diagnostic tools and predictors of response to treatment of neurological developmental disorders (NDD) such as schizophrenia (SZ), attention deficit hyperactivity disorder (ADHD), or autism spectrum disorder (ASD), still remains an important challenge for clinical medicine. Metallomic profiles of ASD patients cover, besides essential elements such as cobalt, chromium, copper, iron, manganese, molybdenum, zinc, selenium, also toxic metals burden of: aluminum, arsenic, mercury, lead, beryllium, nickel, cadmium. Performed studies indicate that children with ASD present a reduced ability of eliminating toxic metals, which leads to these metals' accumulation and aggravation of autistic symptoms. Extensive metallomic studies allow a better understanding of the importance of trace elements as environmental factors in the pathogenesis of ASD. Even though a mineral imbalance is a fact in ASD, we are still expecting relevant tests and the elaboration of reference levels of trace elements as potential biomarkers useful in diagnosis, prevention, and treatment of ASD.

Photobiomodulation by Near-Infrared 980-nm Wavelengths Regulates Pre-Osteoblast Proliferation and Viability through the PI3K/Akt/Bcl-2 Pathway

BACKGROUND

bone tissue regeneration remains a current challenge. A growing body of evidence shows that mitochondrial dysfunction impairs osteogenesis and that this organelle may be the target for new therapeutic options. Current literature illustrates that red and near-infrared light can affect the key cellular pathways of all life forms through interactions with photoacceptors within the cells' mitochondria. The current study aims to provide an understanding of the mechanisms by which photobiomodulation (PBM) by 900-nm wavelengths can induce in vitro molecular changes in pre-osteoblasts.

METHODS

The PubMed, Scopus, Cochrane, and Scholar databases were used. The manuscripts included in the narrative review were selected according to inclusion and exclusion criteria. The new experimental set-up was based on irradiation with a 980-nm laser and a hand-piece with a standard Gaussian and flat-top beam profile. MC3T3-E1 pre-osteoblasts were irradiated at 0.75, 0.45, and 0.20 W in continuous-wave emission mode for 60 s (spot-size 1 cm²) and allowed to generate a power density of 0.75, 0.45, and 0.20 W/cm² and a fluence of 45, 27, and 12 J/cm², respectively. The frequency of irradiation was once, three times (alternate days), or five times (every day) per week for two consecutive weeks. Differentiation, proliferation, and cell viability and their markers were investigated by immunoblotting, immunolabelling, fluorescein-FragELTM-DNA, Hoechst staining, and metabolic activity assays.

RESULTS AND CONCLUSIONS

The 980-nm wavelength can photobiomodulate the pre-osteoblasts, regulating their metabolic schedule. The cellular signal activated by 45 J/cm², 0.75 W and 0.75 W/cm² consist of the PI3K/Akt/Bcl-2 pathway; differentiation markers were not affected, nor do other parameters seem to stimulate the cells. Our previous and present data consistently support the window effect of 980 nm, which has also been described in extracted mitochondria, through activation of signalling PI3K/Akt/Bcl-2 and cyclin family, while the Wnt and Smads 2/3-β-catenin pathway was induced by 55 J/cm², 0.9 W and 0.9 W/cm².

Molecular mechanism of heavy metals (Lead, Chromium, Arsenic, Mercury, Nickel and Cadmium) - induced hepatotoxicity - A review

Heavy metals pose a serious threat if they go beyond permissible limits in our bodies. Much heavy metal's viz. Lead, Chromium, Arsenic, Mercury, Nickel, and Cadmium pose a serious threat when they go beyond permissible limits and cause hepatotoxicity. They cause the generation of ROS which in turn causes numerous injuries and undesirable changes in the liver. Epidemiological studies have shown an increase in the levels of such heavy metals in the environment posing a serious threat to human health. Epigenetic alterations have been seen in the event of exposure to such heavy metals. Apoptosis, caspase activation as well as ultrastructural changes in the hepatocytes have also been seen due to heavy metals. Inflammation involving TNF-alpha, pro-inflammatory cytokines, MAPK, ERK pathways have been seen in the event of heavy metal hepatotoxicity. All these have shown that these heavy metals pose a serious threat to human health in particular and the environment as a whole.

Potential protective roles of curcumin against cadmium-induced toxicity and oxidative stress

Curcumin, used as a spice and traditional medicine in India, exerts beneficial effects against several diseases, owing to its antioxidant, analgesic, and anti-inflammatory properties. Evidence indicates that curcumin might protect against heavy metal-induced organ toxicity by targeting biological pathways involved in anti-oxidation, anti-inflammation, and anti-tumorigenesis. Curcumin has received considerable attention owing to its therapeutic properties, and the mechanisms underlying some of its actions have been recently investigated. Cadmium (Cd) is a heavy metal found in the environment and used extensively in industries. Chronic Cd exposure induces damage to bones, liver, kidneys, lungs, testes, and the immune and cardiovascular systems. Because of its long half-life, exposure to even low Cd levels might be harmful. Cd-induced toxicity involves the overproduction of reactive oxygen species (ROS), resulting in oxidative stress and damage to essential biomolecules. Dietary antioxidants, such as chelating agents, display the potential to reduce Cd accumulation and metal-induced toxicity. Curcumin scavenges ROS and inhibits oxidative damage, thus resulting in many therapeutic properties. This review aims to address the effectiveness of curcumin against Cd-induced organ toxicity and presents evidence supporting the use of curcumin as a protective antioxidant.

Immunohistochemical, histopathological, and biochemical studies of the NF-ҡB P65 marker in rat ovaries experimentally intoxicated by cadmium and the protective effect of the purslane plant extract

The aim of this study is to describe the existence of the inflammatory marker nuclear factor kappa light chain B lymphocyte protein (NF-ҡB P65) in the tissue as a response to cadmium (CdCl₂) toxicity. Next is to describe the disappearance of the NF-ҡB P65 in response to the purslane plant treatment to explore its anti-inflammatory effect, also describing the histopathological and biochemical changes that occurred from CdCl₂ toxicity and the purslane plant tissue protections. There are four experimental groups, 32 rats (n = 8) intraperitoneally injected with CdCl₂ and orally administered with purslane plant extract (according to groups) for 30 days: group one (control), group two (purslane extract 2 g/kg bw), group three (CdCl₂ 3.5 mg/kg bw), group four (CdCl₂ 3.5 mg/kg bw + purslane plant extract 2 g/kg bw). The biochemical findings showed that ovaries and brain tissue homogenates in group three showed malondialdehyde increase and reduction in catalase, total antioxidant capacity, and acetylcholine esterase. A reduction in serum LH, FSH, and estradiol were also recorded. These parameters became normal in group four. The histopathological findings exhibited that group three showed ovarian and cerebral hemorrhage and lung pneumonia. Tissues of group four were protected and no pathological lesions were detected. The immunohistochemical results showed that the inflammatory marker NF-ҡB P65 in group three was strongly detected in the spleen and moderately detected in the ovaries, brain, and lung but negatively detected in the tissues of group four. In conclusion, CdCl₂ induced ovarian toxicity and the NF-ҡB P65 existence was increased. Purslane plant protected rats from CdCl₂ toxicity and decrease NF-ҡB P65.

Evaluation of Punarnavadi Mandura for haematinic activity against mercuric chloride-induced anemia in albino rats

Background

Punarnavadi Mandura, a compound Ayurvedic formulation, is one of the most commonly used medicine in the treatment of anemia (Pandu) in Ayurveda. The safety profile of this formulation is well established; however, no pharmacological study has been reported to provide the scientific basis for its use in the treatment of anemia.

Aim

To evaluate the hematinic effect of Punarnavadi Mandura against mercuric chloride-induced anemia in albino rats.

Materials and methods

The test drug (Punarnavadi Mandura) was suspended in distilled water and administered orally in a dose of 450 mg/kg for 30 days in rats. Anemia was induced by simultaneous administration of mercuric chloride (9 mg/kg) for 30 consecutive days. Body weight was noted for each animals. At the end, haematological parameters, anaemia markers like serum iron, ferritin, and total iron binding capacity (TIBC), as well as relative weight of organs and histopathology investigation, were examined.

Results

Exposure of mercuric chloride to rats for 30 days resulted in a significant decrease of body weight, an increase in the weight of the liver and kidney and a decrease in hemoglobin content. It also decreased serum ferritin to a significant extent and increased serum TIBC. Histopathology of the liver shows macro fatty changes, vacuolization, marked necrosis, and severe degenerative changes, while the kidney shows cell infiltration. All these changes were significantly attenuated by the administration of Punarnavadi Mandura.

Conclusion

The present data indicate that Punarnavadi Mandura has possessing marked cytoprotective activity, significantly attenuated the HgCl2-induced adverse changes on red blood cell related parameters, and showing hematinic activity in albino rats.