The role of metallothionein in oxidative stress

Navigating the redox landscape: reactive oxygen species in regulation of cell cycle

Objectives: To advance our knowledge of disease mechanisms and therapeutic options, understanding cell cycle regulation is critical. Recent research has highlighted the importance of reactive oxygen species (ROS) in cell cycle regulation. Although excessive ROS levels can lead to age-related pathologies, ROS also play an essential role in normal cellular functions. Many cell cycle regulatory proteins are affected by their redox status, but the precise mechanisms and conditions under which ROS promote or inhibit cell proliferation are not fully understood.Methods: This review presents data from the scientific literature and publicly available databases on changes in redox state during the cell cycle and their effects on key regulatory proteins.Results: We identified redox-sensitive targets within the cell cycle machinery and analysed different effects of ROS (type, concentration, duration of exposure) on cell cycle phases. For example, moderate levels of ROS can promote cell proliferation by activating signalling pathways involved in cell cycle progression, whereas excessive ROS levels can induce DNA damage and trigger cell cycle arrest or cell death.Discussion: Our findings encourage future research focused on identifying redox-sensitive targets in the cell cycle machinery, potentially leading to new treatments for diseases with dysregulated cell proliferation.

LATS1 inhibitor and zinc supplement synergistically ameliorates contrast-induced acute kidney injury: Induction of Metallothionein-1 and suppression of tubular ferroptosis

Contrast-induced acute kidney injury (CI-AKI) is a prevalent cause of renal dysfunction among hospitalized patients, yet the precise pathogenesis and effective therapeutic strategies remain elusive. In this study, we investigated the role of tubular ferroptosis in both experimental CI-AKI models and in primary tubular epithelial cells (PTECs) treated with ioversol. Using whole exome sequencing, we identified metallothioneins (MTs) as being among the most significantly downregulated genes following ioversol exposure. Our findings reveal that overexpression of Mt1 mitigates, whereas suppression of Mt-1 exacerbates, ioversol-induced tubular ferroptosis. Interestingly, the level of MTF1 (metal regulatory transcription factor 1), a principal regulator of Mt1, was found to increase in response to ioversol treatment. We further elucidated that ioversol activates LATS1 (Large tumor suppressor homolog 1), a kinase that promotes the phosphorylation and nuclear translocation of MTF1, thereby inhibiting its transcriptional activity for Mt1. Both genetic and pharmacological inhibition of LATS1 reversed the ioversol-induced suppression of Mt-1. From a therapeutic perspective, the LATS1 inhibitor TDI-011536, in combination with zinc acetate, was administered to a rodent model of CI-AKI. Our data indicate that this combination synergistically upregulates Mt1 expression and provides protection against contrast media-induced tubular ferroptosis. In summary, our study demonstrates that the reduction of Mt-1 contributes to tubular ferroptosis associated with CI-AKI. We show that contrast media activate LATS1, which in turn suppresses the transcriptional activity of MTF1 for Mt1. Herein, the combination of zinc acetate and a LATS1 inhibitor emerges as a potential therapeutic approach for the treatment of CI-AKI.

Cadmium exposure and its association with oxidative stress, MT1A methylation, and idiopathic male infertility in Egypt: A case-control study

Idiopathic male infertility, a significant health concern, lacks a clear etiology. Cadmium (Cd), a widespread environmental pollutant known to impact male reproductive health negatively, can accumulate in mussels, a common food source in Egypt. This study investigated the link between ecological Cd exposure, oxidative stress, MT1A methylation, and idiopathic male infertility in two regions of Alexandria. Thirty-three infertile men and 33 fertile controls were included. Cd levels were measured in mussels from the study sites and in participants' blood and semen. Biomarkers reflecting Cd exposure and its effects were assessed. Mussel Cd levels exceeded regulatory limits. Infertile men revealed significantly higher blood and semen Cd levels, reduced semen quality, increased oxidative stress, and elevated MT1A methylation compared to controls. MT1A methylation was inversely correlated with sperm count and is the strongest predictor of idiopathic male infertility, demonstrating the lowest p-value and considerable effect size. This study suggests that environmental Cd exposure, potentially through mussel consumption, may contribute to idiopathic male infertility in Egypt by increasing oxidative stress, inducing epigenetic modifications, and impairing semen quality. These findings underscore the need for further research into the mechanisms underlying Cd-induced male infertility and the development of preventative strategies.

Increased spontaneous activity and progressive suppression of adult neurogenesis in the hippocampus of rat offspring after maternal exposure to imidacloprid

Imidacloprid (IMI) is a widely used neonicotinoid insecticide that poses risks for developmental neurotoxicity in mammals. The present study investigated the effects of maternal exposure to IMI on behaviors and adult neurogenesis in the hippocampal dentate gyrus (DG) of rat offspring. Dams were exposed to IMI via diet (83, 250, or 750 ppm in diet) from gestational day 6 until day 21 post-delivery on weaning, and offspring were maintained until adulthood on postnatal day 77. In the neurogenic niche, 750-ppm IMI decreased numbers of late-stage neural progenitor cells (NPCs) and post-mitotic immature granule cells by suppressing NPC proliferation and ERK1/2-FOS-mediated synaptic plasticity of granule cells on weaning. Suppressed reelin signaling might be responsible for the observed reductions of neurogenesis and synaptic plasticity. In adulthood, IMI at ≥ 250 ppm decreased neural stem cells by suppressing their proliferation and increasing apoptosis, and mature granule cells were reduced due to suppressed NPC differentiation. Behavioral tests revealed increased spontaneous activity in adulthood at 750 ppm. IMI decreased hippocampal acetylcholinesterase activity and Chrnb2 transcript levels in the DG on weaning and in adulthood. IMI increased numbers of astrocytes and M1-type microglia in the DG hilus, and upregulated neuroinflammation and oxidative stress-related genes on weaning. In adulthood, IMI increased malondialdehyde level and number of M1-type microglia, and downregulated neuroinflammation and oxidative stress-related genes. These results suggest that IMI persistently affected cholinergic signaling, induced neuroinflammation and oxidative stress during exposure, and increased sensitivity to oxidative stress after exposure in the hippocampus, causing hyperactivity and progressive suppression of neurogenesis in adulthood. The no-observed-adverse-effect level of IMI for offspring behaviors and hippocampal neurogenesis was determined to be 83 ppm (5.5-14.1 mg/kg body weight/day).

Thymidylate synthase disruption to limit cell proliferation in cell therapies

Stem and progenitor cells hold great promise for regenerative medicine and gene therapy approaches. However, transplantation of living cells entails a fundamental risk of unwanted growth, potentially exacerbated by CRISPR-Cas9 or other genetic manipulations. Here, we describe a safety system to control cell proliferation while allowing robust and efficient cell manufacture, without any added genetic elements. Inactivating TYMS, a key nucleotide metabolism enzyme, in several cell lines resulted in cells that proliferate only when supplemented with exogenous thymidine. Under supplementation, TYMS-/--pluripotent stem cells proliferate, produce teratomas, and successfully differentiate into potentially therapeutic cell types such as pancreatic β cells. Our results suggest that supplementation with exogenous thymidine affects stem cell proliferation, but not the function of stem cell-derived cells. After differentiation, postmitotic cells do not require thymidine in vitro or in vivo, as shown by the production of functional human insulin in mice up to 5 months after implantation of stem cell-derived pancreatic tissue.

Spatial transcriptomics reveals organized and distinct immune activation in cutaneous granulomatous disorders

BACKGROUND

Noninfectious (inflammatory) cutaneous granulomatous disorders include cutaneous sarcoidosis (CS), granuloma annulare (GA), necrobiosis lipoidica (NL), and necrobiotic xanthogranuloma (NXG). These disorders share macrophage-predominant inflammation histologically, but the inflammatory architecture and the pattern of extracellular matrix alteration varies. The underlying molecular explanations for these differences remain unclear.

OBJECTIVE

We sought to understand spatial gene expression characteristics in these disorders.

METHODS

We performed spatial transcriptomics in cases of CS, GA, NL, and NXG to compare patterns of immune activation and other molecular features in a spatially resolved fashion.

RESULTS

CS is characterized by a polarized, spatially organized type 1-predominant response with classical macrophage activation. GA is characterized by a mixed but spatially organized pattern of type 1 and type 2 polarization with both classical and alternative macrophage activation. NL showed concomitant activation of type 1, type 2, and type 3 immunity with a mixed pattern of macrophage activation. Activation of type 1 immunity was shared among, CS, GA, and NL and included upregulation of IL-32. NXG showed upregulation of CXCR4-CXCL12/14 chemokine signaling and exaggerated alternative macrophage polarization. Histologic alteration of extracellular matrix correlated with hypoxia and glycolysis programs and type 2 immune activation.

CONCLUSIONS

Inflammatory cutaneous granulomatous disorders show distinct and spatially organized immune activation that correlate with hallmark histologic changes.

Antioxidant-related enzymes and peptides as biomarkers of metallic nanoparticles (eco)toxicity in the aquatic environment

Increased awareness of the impact of human activities on the environment has emerged in recent decades. One significant global environmental and human health issue is the development of materials that could potentially have negative effects. These materials can accumulate in the environment, infiltrate organisms, and move up the food chain, causing toxic effects at various levels. Therefore, it is crucial to assess materials comprising nano-scale particles due to the rapid expansion of nanotechnology. The aquatic environment, particularly vulnerable to waste pollution, demands attention. This review provides an overview of the behavior and fate of metallic nanoparticles (NPs) in the aquatic environment. It focuses on recent studies investigating the toxicity of different metallic NPs on aquatic organisms, with a specific emphasis on thiol-biomarkers of oxidative stress such as glutathione, thiol- and related-enzymes, and metallothionein. Additionally, the selection of suitable measurement methods for monitoring thiol-biomarkers in NPs' ecotoxicity assessments is discussed. The review also describes the analytical techniques employed for determining levels of oxidative stress biomarkers.

Interactions of binary mixtures of metals on rainbow trout (Oncorhynchus mykiss) heart mitochondrial H2O2 homeodynamics

For continuous pumping of blood, the heart needs a constant supply of energy (ATP) that is primarily met via oxidative phosphorylation in the mitochondria of cardiomyocytes. However, sustained high rates of electron transport for energy conversion redox reactions predisposes the heart to the production of reactive oxygen species (ROS) and oxidative stress. Mitochondrial ROS are fundamental drivers of responses to environmental stressors including metals but knowledge of how combinations of metals alter mitochondrial ROS homeodynamics remains sparse. We explored the effects and interactions of binary mixtures of copper (Cu), cadmium (Cd), and zinc (Zn), metals that are common contaminants of aquatic systems, on ROS (hydrogen peroxide, H2O2) homeodynamics in rainbow trout (Oncorhynchus mykiss) heart mitochondria. Isolated mitochondria were energized with glutamate-malate or succinate and exposed to a range of concentrations of the metals singly and in equimolar binary concentrations. Speciation analysis revealed that Cu was highly complexed by glutamate or Tris resulting in Cu2+ concentrations in the picomolar to nanomolar range. The concentration of Cd2+ was 7.2-7.5 % of the total while Zn2+ was 15 % and 21 % of the total during glutamate-malate and succinate oxidation, respectively. The concentration-effect relationships for Cu and Cd on mitochondrial H2O2 emission depended on the substrate while those for Zn were similar during glutamate-malate and succinate oxidation. Cu + Zn and Cu + Cd mixtures exhibited antagonistic interactions wherein Cu reduced the effects of both Cd and Zn, suggesting that Cu can mitigate oxidative distress caused by Cd or Zn. Binary combinations of the metals acted additively to reduce the rate constant and increase the half-life of H2O2 consumption while concomitantly suppressing thioredoxin reductase and stimulating glutathione peroxidase activities. Collectively, our study indicates that binary mixtures of Cu, Zn, and Cd act additively or antagonistically to modulate H2O2 homeodynamics in heart mitochondria.

Expression and Functional Analysis of the Metallothionein and Metal-Responsive Transcription Factor 1 in Phascolosoma esculenta under Zn Stress

Metallothioneins (MTs) are non-enzymatic metal-binding proteins widely found in animals, plants, and microorganisms and are regulated by metal-responsive transcription factor 1 (MTF1). MT and MTF1 play crucial roles in detoxification, antioxidation, and anti-apoptosis. Therefore, they are key factors allowing organisms to endure the toxicity of heavy metal pollution. Phascolosoma esculenta is a marine invertebrate that inhabits intertidal zones and has a high tolerance to heavy metal stress. In this study, we cloned and identified MT and MTF1 genes from P. esculenta (designated as PeMT and PeMTF1). PeMT and PeMTF1 were widely expressed in all tissues and highly expressed in the intestine. When exposed to 16.8, 33.6, and 84 mg/L of zinc ions, the expression levels of PeMT and PeMTF1 in the intestine increased first and then decreased, peaking at 12 and 6 h, respectively, indicating that both PeMT and PeMTF1 rapidly responded to Zn stress. The recombinant pGEX-6p-1-MT protein enhanced the Zn tolerance of Escherichia coli and showed a dose-dependent ABTS free radical scavenging ability. After RNA interference (RNAi) with PeMT and 24 h of Zn stress, the oxidative stress indices (MDA content, SOD activity, and GSH content) and the apoptosis indices (Caspase 3, Caspase 8, and Caspase 9 activities) were significantly increased, implying that PeMT plays an important role in Zn detoxification, antioxidation, and anti-apoptosis. Moreover, the expression level of PeMT in the intestine was significantly decreased after RNAi with PeMTF1 and 24 h of Zn stress, which preliminarily proved that PeMTF1 has a regulatory effect on PeMT. Our data suggest that PeMT and PeMTF1 play important roles in the resistance of P. esculenta to Zn stress and are the key factors allowing P. esculenta to endure the toxicity of Zn.

Renoprotective effect of hyperin against CdCl2 prompted renal damage by activation of Nrf-2/Keap-1 ARE pathway in male mice

OBJECTIVES

This study explored the mitigating properties of hyperin (HYP) on renotoxicity induced by cadmium chloride (CdCl2).

METHODS

Four groups of seven male albino mice each were used in this experiment. Group 1 served as the control, receiving no treatment. Group 2 received daily oral gavage of CdCl2 at 0.3 mg/kg body weight for 28 d. Group 3 received both CdCl2 (0.3 mg/kg) and HYP (100 mg/kg) daily using the same administration method. Finally, Group 4 received only HYP (100 mg/kg) daily.

RESULTS

Cd exposure significantly increased kidney dysfunction markers (blood urea nitrogen and creatinine) and oxidative stress (reactive oxygen species [ROS] and malondialdehyde [MDA]). Conversely, it decreased antioxidant enzyme activities (glutathione peroxidase (GPx] and catalase [CAT]) and glutathione (GSH) levels. Nuclear factor erythroid 2-related factor 2 (Nrf-2) and antioxidant gene expression decreased, while Kelch-like ECH-associated protein 1 expression increased. Additionally, Cd exposure increased inflammatory mediators (nuclear factor kappa B, tumor necrosis factor alpha [TNF-α], interleukin-1β [IL-1β], and cyclooxygenase-2) and apoptotic markers (Bax and caspase-3), alongside decreased Bcl-2 expression and renal tissue abnormalities. Mitochondrial dysfunction manifested with diminished activities of Krebs cycle and respiratory chain enzymes, and reduced mitochondrial membrane potential. Co-treatment with HYP significantly attenuated these detrimental effects through its anti-apoptotic, antioxidant, and anti-inflammatory properties.

CONCLUSION

HYP co-treatment significantly attenuated CdCl2-induced renal damage in mice, suggesting its potential as a protective agent against Cd-induced kidney toxicity.

A metallothionein from disk abalone (Haliotis discus discus): Insights into its functional roles in immune response, metal tolerance, and oxidative stress

Metallothioneins (MTs) are cysteine-rich metal-binding proteins whose expression is induced by exposure to essential and non-essential metals, making them potential biological markers for assessing metal pollution in various biomonitoring programs. However, the functional properties of these proteins are yet to be comprehensively characterized in most marine invertebrates. In this study, we identified and characterized an MT homolog from the disk abalone (Haliotis discus discus), referred to as disk abalone MT (AbMT). AbMT exhibited the same primary structural features as MTs from other mollusks containing two β-domains (β2β1-form). AbMT protein demonstrated metal-binding and detoxification abilities against Zn, Cu, and Cd, as evidenced by Escherichia coli growth kinetics, metal tolerance analysis, and UV absorption spectrum. Transcriptional analysis revealed that AbMT was ubiquitously expressed in all analyzed tissues and upregulated in gill tissue following challenge with Vibrio parahaemolyticus, Listeria monocytogenes, and viral hemorrhagic septicemia virus (VHSV). Additionally, overexpression of AbMT suppressed LPS-induced NO production in RAW264.7 macrophages, protected cells against H2O2-induced oxidative stress, and promoted macrophage polarization toward the M1 phase. Conclusively, these findings suggest an important role for AbMT in environmental stress protection and immune regulation in disk abalone.

Zinc Toxicity: Understanding the Limits

Zinc, a vital trace element, holds significant importance in numerous physiological processes within the body. It participates in over 300 enzymatic reactions, metabolic functions, regulation of gene expression, apoptosis and immune modulation, thereby demonstrating its essential role in maintaining overall health and well-being. While zinc deficiency is associated with significant health risks, an excess of this trace element can also lead to harmful effects. According to the World Health Organization (WHO), 6.7 to 15 mg per day are referred to be the dietary reference value. An excess of the recommended daily intake may result in symptoms such as anemia, neutropenia and zinc-induced copper deficiency. The European Food Safety Authority (EFSA) defines the tolerable upper intake level (UL) as 25 mg per day, whereas the Food and Drug Administration (FDA) allows 40 mg per day. This review will summarize the current knowledge regarding the calculation of UL and other health risks associated with zinc. For example, zinc intake is not limited to oral consumption; other routes, such as inhalation or topical application, may also pose risks of zinc intoxication.

Disulfiram: A novel repurposed drug for cancer therapy

ABSTRACT

Cancer is a major global health issue. Effective therapeutic strategies can prolong patients' survival and reduce the costs of treatment. Drug repurposing, which identifies new therapeutic uses for approved drugs, is a promising approach with the advantages of reducing research costs, shortening development time, and increasing efficiency and safety. Disulfiram (DSF), a Food and Drug Administration (FDA)-approved drug used to treat chronic alcoholism, has a great potential as an anticancer drug by targeting diverse human malignancies. Several studies show the antitumor effects of DSF, particularly the combination of DSF and copper (DSF/Cu), on a wide range of cancers such as glioblastoma (GBM), breast cancer, liver cancer, pancreatic cancer, and melanoma. In this review, we summarize the antitumor mechanisms of DSF/Cu, including induction of intracellular reactive oxygen species (ROS) and various cell death signaling pathways, and inhibition of proteasome activity, as well as inhibition of nuclear factor-kappa B (NF-κB) signaling. Furthermore, we highlight the ability of DSF/Cu to target cancer stem cells (CSCs), which provides a new approach to prevent tumor recurrence and metastasis. Strikingly, DSF/Cu inhibits several molecular targets associated with drug resistance, and therefore it is becoming a novel option to increase the sensitivity of chemo-resistant and radio-resistant patients. Studies of DSF/Cu may shed light on its improved application to clinical tumor treatment.

The different impact of drug-resistant Leishmania on the transcription programs activated in neutrophils

Drug resistance threatens the effective control of infections, including parasitic diseases such as leishmaniases. Neutrophils are essential players in antimicrobial control, but their role in drug-resistant infections is poorly understood. Here, we evaluated human neutrophil response to clinical parasite strains having distinct natural drug susceptibility. We found that Leishmania antimony drug resistance significantly altered the expression of neutrophil genes, some of them transcribed by specific neutrophil subsets. Infection with drug-resistant parasites increased the expression of detoxification pathways and reduced the production of cytokines. Among these, the chemokine CCL3 was predominantly impacted, which resulted in an impaired ability of neutrophils to attract myeloid cells. Moreover, decreased myeloid recruitment when CCL3 levels are reduced was confirmed by blocking CCL3 in a mouse model. Collectively, these findings reveal that the interplay between naturally drug-resistant parasites and neutrophils modulates the infected skin immune microenvironment, revealing a key role of neutrophils in drug resistance.

IL-17C is a driver of damaging inflammation during Neisseria gonorrhoeae infection of human Fallopian tube

The human pathogen Neisseria gonorrhoeae ascends into the upper female reproductive tract to cause damaging inflammation within the Fallopian tubes and pelvic inflammatory disease (PID), increasing the risk of infertility and ectopic pregnancy. The loss of ciliated cells from the epithelium is thought to be both a consequence of inflammation and a cause of adverse sequelae. However, the links between infection, inflammation, and ciliated cell extrusion remain unresolved. With the use of ex vivo cultures of human Fallopian tube paired with RNA sequencing we defined the tissue response to gonococcal challenge, identifying cytokine, chemokine, cell adhesion, and apoptosis related transcripts not previously recognized as potentiators of gonococcal PID. Unexpectedly, IL-17C was one of the most highly induced genes. Yet, this cytokine has no previous association with gonococcal infection nor pelvic inflammatory disease and thus it was selected for further characterization. We show that human Fallopian tubes express the IL-17C receptor on the epithelial surface and that treatment with purified IL-17C induces pro-inflammatory cytokine secretion in addition to sloughing of the epithelium and generalized tissue damage. These results demonstrate a previously unrecognized but critical role of IL-17C in the damaging inflammation induced by gonococci in a human explant model of PID.

Cuproptosis: unveiling a new frontier in cancer biology and therapeutics

Copper plays vital roles in numerous cellular processes and its imbalance can lead to oxidative stress and dysfunction. Recent research has unveiled a unique form of copper-induced cell death, termed cuproptosis, which differs from known cell death mechanisms. This process involves the interaction of copper with lipoylated tricarboxylic acid cycle enzymes, causing protein aggregation and cell death. Recently, a growing number of studies have explored the link between cuproptosis and cancer development. This review comprehensively examines the systemic and cellular metabolism of copper, including tumor-related signaling pathways influenced by copper. It delves into the discovery and mechanisms of cuproptosis and its connection to various cancers. Additionally, the review suggests potential cancer treatments using copper ionophores that induce cuproptosis, in combination with small molecule drugs, for precision therapy in specific cancer types.

Sphingolipid biosynthetic inhibitor L-Cycloserine prevents oxidative-stress-mediated death in an in vitro model of photoreceptor-derived 661W cells

Oxidative stress plays a pivotal role in the pathogenesis of several neurodegenerative diseases. Retinal degeneration causes irreversible death of photoreceptor cells, ultimately leading to vision loss. Under oxidative stress, the synthesis of bioactive sphingolipid ceramide increases, triggering apoptosis in photoreceptor cells and leading to their death. This study investigates the effect of L-Cycloserine, a small molecule inhibitor of ceramide biosynthesis, on sphingolipid metabolism and the protection of photoreceptor-derived 661W cells from oxidative stress. The results demonstrate that treatment with L-Cycloserine, an inhibitor of Serine palmitoyl transferase (SPT), markedly decreases bioactive ceramide and associated sphingolipids in 661W cells. A nontoxic dose of L-Cycloserine can provide substantial protection of 661W cells against H2O2-induced oxidative stress by reversing the increase in ceramide level observed under oxidative stress conditions. Analysis of various antioxidant, apoptotic and sphingolipid pathway genes and proteins also confirms the ability of L-Cycloserine to modulate these pathways. Our findings elucidate the generation of sphingolipid mediators of cell death in retinal cells under oxidative stress and the potential of L-Cycloserine as a therapeutic candidate for targeting ceramide-induced degenerative diseases by inhibiting SPT. The promising therapeutic prospect identified in our findings lays the groundwork for further validation in in-vivo and preclinical models of retinal degeneration.

Identification of a distinct cluster of GDF15high macrophages induced by in vitro differentiation exhibiting anti-inflammatory activities

Introduction

Macrophage-mediated inflammatory response may have crucial roles in the pathogenesis of a variety of human diseases. Growth differentiation factor 15 (GDF15) is a cytokine of the transforming growth factor-β superfamily, with potential anti-inflammatory activities. Previous studies observed in human lungs some macrophages which expressed a high level of GDF15.

Methods

In the present study, we employed multiple techniques, including immunofluorescence, flow cytometry, and single-cell RNA sequencing, in order to further clarify the identity of such GDF15high macrophages.

Results

We demonstrated that macrophages derived from human peripheral blood mononuclear cells and rat bone marrow mononuclear cells by in vitro differentiation with granulocyte-macrophage colony stimulating factor contained a minor population (~1%) of GDF15high cells. GDF15high macrophages did not exhibit a typical M1 or M2 phenotype, but had a unique molecular signature as revealed by single-cell RNA sequencing. Functionally, the in vitro derived GDF15high macrophages were associated with reduced responsiveness to pro-inflammatory activation; furthermore, these GDF15high macrophages could inhibit the pro-inflammatory functions of other macrophages via a paracrine mechanism. We further confirmed that GDF15 per se was a key mediator of the anti-inflammatory effects of GDF15high macrophage. Also, we provided evidence showing that GDF15high macrophages were present in other macrophage-residing human tissues in addition to the lungs. Further scRNA-seq analysis in rat lung macrophages confirmed the presence of a GDF15high sub-population. However, these data indicated that GDF15high macrophages in the body were not a uniform population based on their molecular signatures. More importantly, as compared to the in vitro derived GDF15high macrophage, whether the tissue resident GDF15high counterpart is also associated with anti-inflammatory functions remains to be determined. We cannot exclude the possibility that the in vitro priming/induction protocol used in our study has a determinant role in inducing the anti-inflammatory phenotype in the resulting GDF15high macrophage cells.

Conclusion

In summary, our results suggest that the GDF15high macrophage cells obtained by in vitro induction may represent a distinct cluster with intrinsic anti-inflammatory functions. The (patho)physiological importance of these cells in vivo warrants further investigation.

Zinc Supplementation Reduces Testicular Cell Apoptosis in Mice and Improves Spermatogenic Dysfunction Caused by Marginal Zinc Deficiency

Zinc (Zn) is an important trace element in the human body and plays an important role in growth, development, and male reproductive functions. Marginal zinc deficiency (MZD) is common in the human population and can cause spermatogenic dysfunction in males. Therefore, the aim of this study was to investigate methods to improve spermatogenic dysfunction caused by MZD and to further explore its mechanism of action. A total of 75 4-week-old male SPF ICR mice were randomly divided into five groups (control, MZD, MZD + ZnY2, MZD + ZnY4, and MZD + ZnY8, 15 mice per group). The dietary Zn content was 30 mg/kg in the control group and 10 mg/kg in the other groups. From low to high, the Zn supplementation doses administered to the three groups were 2, 4, and 8 mg/kg·bw. After 35 days, the zinc content, sperm quality, activity of spermatogenic enzymes, oxidative stress level, and apoptosis level of the testes in mice were determined. The results showed that MZD decreased the level of Zn in the serum, sperm quality, and activity of spermatogenic enzymes in mice. After Zn supplementation, the Zn level in the serum increased, sperm quality was significantly improved, and spermatogenic enzyme activity was restored. In addition, MZD reduced the content of antioxidants (copper-zinc superoxide dismutase (Cu-Zn SOD), metallothionein (MT), and glutathione (GSH) and promoted malondialdehyde (MDA) production. The apoptosis index of the testis also increased significantly in the MZD group. After Zn supplementation, the level of oxidative stress decreased, and the apoptosis index in the testis was reduced. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) showed that the expression of B-cell lymphoma-2 (Bcl-2) mRNA and Bcl-2/BCL2-associated X (Bax) in the control group decreased in testicular cells, and their expression was restored after Zn supplementation. The results of this study indicated that Zn supplementation can reduce the level of oxidative stress and increase the ability of testicular cells to resist apoptosis, thereby improving spermatogenic dysfunction caused by MZD in mice.

Foraging Activity of Honey Bees (Apis mellifera L., 1758) and Exposure to Cadmium: a Review

Honey bees are commonly exposed to a broad spectrum of xenobiotics, including heavy metals. Heavy metal toxicity is of concern in the context of global pollinator declines, especially since honey bees seem to be particularly susceptible to xenobiotics in general. Here we summarize current knowledge on the interplay between cadmium, one of the most toxic and mobile elements in the environment, and honey bees, the primary managed pollinator species worldwide. Overall, cadmium pollution has been shown to be ubiquitous, affecting industrial, urban and rural areas alike. Uptake of this heavy metal by plants serves as the primary route of exposure for bees (through pollen and nectar). Reported cadmium toxicity consists of lethal and sublethal effects (reduced development and growth) in both adult and larval stages, as well as various molecular responses related to detoxification and cellular antioxidant defence systems. Other effects of cadmium in honey bees include the disruption of synaptic signalling, calcium metabolism and muscle function.

Preparation of a novel metallothionein-AuNP composite material by genetic modification and AuS covalent combination

Metallothionein (MTs) can be used in the prevention and treatment of tumors and diabetes due to its antioxidant properties. However, it is necessary to solve its non-transmembrane properties and further improve its antioxidant activity, increase its fluorescence visualization and enhance its stability to meet practical applications in the biomedical field. Here, we report the preparation of a novel metallothionein-AuNP composite material with high transmembrane ability, fluorescence visualization, antioxidant activity, and stability by genetic modification (introducing transduction peptide TAT, fluorescence tag GFP and increasing sulfydryl groups) and immobilization technology (covalently bonding with AuNPs). The transmembrane activity of modified proteins was verified by immunofluorescence. Increasing the sulfhydryl content within a certain range can enhance the antioxidant activity of the protein. In addition, GFP were used to further simplify the imaging of the metallothionein-AuNP composite in cells. XPS results indicated that AuNPs can immobilize metallothionein through AuS covalent bonds. TGA characterization and degradation experiments showed that thermal and degradation stability of the immobilized material was significantly improved. This work provides new ideas to construct metallothionein composites with high transmembrane ability, antioxidant activity, fluorescence visualization and stability to meet novel applications in the biomedical field.

The toxicity assessment of phosmet on development, reproduction, and gene expression in Daphnia magna

The use of pesticides to control pests, weeds, and diseases or to regulate plant growth is indispensable in agricultural production. However, the excessive use of these chemicals has led to significant concern about their potential negative impacts on health and the environment. Phosmet is one such pesticide that is commonly used on plants and animals against cold moth, aphids, mites, suckers, and fruit flies. Here, we investigated the effects of phosmet on a model organism, Daphnia magna using acute and chronic toxicity endpoints such as lethality, mobility, genotoxicity, reproduction, and gene expression. We performed survival experiments in six-well plates at seven different concentrations (0.01, 0.1, 1, 10, 25, 50, 100 μM) as well as the control in three replicates. We observed statistically significant mortality rates at 25 µM and above upon 24 h of exposure, and at 1 µM and above following 48 h of exposure. Genotoxicity analysis, reproduction assay and qPCR analysis were carried out at concentrations of 0.01 and 0.1 μM phosmet as these concentrations did not show any lethality. Comet assay showed that exposure to phosmet resulted in significant DNA damage in the cells. Interestingly, 0.1 μM phosmet produced more offspring per adult compared to the control group indicating a hormetic response. Gene expression profiles demonstrated several genes involved in different physiological pathways, including oxidative stress, detoxification, immune system, hypoxia and iron homeostasis. Taken together, our results indicate that phosmet has negative effects on Daphnia magna in a dose- and time-dependent manner and could also induce lethal and physiological toxicities to other aquatic organisms.

Protective Potential of a Botanical-Based Supplement Ingredient against the Impact of Environmental Pollution on Cutaneous and Cardiopulmonary Systems: Preclinical Study

Air pollution is a growing threat to human health. Airborne pollution effects on respiratory, cardiovascular and skin health are well-established. The main mechanisms of air-pollution-induced health effects involve oxidative stress and inflammation. The present study evaluates the potential of a polyphenol-enriched food supplement ingredient comprising Lippia citriodora, Olea europaea, Rosmarinus officinalis, and Sophora japonica extracts in mitigating the adverse effects of environmental pollution on skin and cardiopulmonary systems. Both in vitro and ex vivo studies were used to assess the blend's effects against pollution-induced damage. In these studies, the botanical blend was found to reduce lipid peroxidation, inflammation (by reducing IL-1α), and metabolic alterations (by regulating MT-1H, AhR, and Nrf2 expression) in human skin explants exposed to a mixture of pollutants. Similar results were also observed in keratinocytes exposed to urban dust. Moreover, the ingredient significantly reduced pollutant-induced ROS production in human endothelial cells and lung fibroblasts, while downregulating the expression of apoptotic genes (bcl-2 and bax) in lung fibroblasts. Additionally, the blend counteracted the effect of urban dust on the heart rate in zebrafish embryos. These results support the potential use of this supplement as an adjuvant method to reduce the impact of environmental pollution on the skin, lungs, and cardiovascular tissues.

Chlorpromazine's impact on Mytilus galloprovincialis: a multi-faceted investigation

The antipsychotic chlorpromazine (Cpz) has raised concern as a pharmaceutical effluent due to its wide medical applications. Moreover, its potent pro-oxidant properties and impact on the cell viability of the marine mollusc Mytilus galloprovincialis, even at low concentrations (ng/L), have been noted. Based on this evidence, in this study, we investigated the physiological effects of Cpz on M. galloprovincialis, to elucidate its fate within the organism, in terms of bioaccumulation, biotransformation, byssus changes and stress responses of the cellular thiolome. Histological and indicators of vitality analyses were also performed to better evaluate the influence of the drug on the morphology and cell viability of the digestive gland. To this end, two different concentrations of Cpz (Cpz I (12 ng/L or 37 pM) and Cpz II (12 μg/L or 37 nM)) were administered to mussels over 14 days. Cpz accumulation in the digestive gland significantly increased with water concentration (BCF of Cpz I and Cpz II). Biochemical analyses indicated lysosomal dysfunction, reflected in elevated total Cathepsin D activity and compromised lysosomal membrane stability. Stress-related and metal-buffering proteins (GST and metallothionein) responded to both Cpz concentrations. Cpz I induced phase I biotransformation activity (CYP450-dependent EROD), while Cpz II triggered caspase-3 activation, indicative of detoxification overload. Histological analysis revealed digestive gland atrophy, epithelial thinning, haemocyte infiltration, and brown cell presence. Byssus analysis showed significant alterations. In conclusion, our study underscores Cpz-induced physiological and histological changes in M. galloprovincialis, posing potential implications for mussel health and confirming the utilisation of this mussel as an indication of Cpz ecotoxicity.

Mechanism of cadmium-induced nephrotoxicity

Heavy metals are found naturally in our environment and have many uses and applications in daily life. However, high concentrations of metals may be a result of pollution due to industrialization. In particular, cadmium (Cd), a white metal abundantly distributed in the terrestrial crust, is found in mines together with zinc, which accumulates after volcanic eruption or is found naturally in the sea and earth. High levels of Cd have been associated with disease. In the human body, Cd accumulates in two ways: via inhalation or consumption, mainly of plants or fish contaminated with high concentrations. Several international organizations have been working to establish the limit values of heavy metals in food, water, and the environment to avoid their toxic effects. Increased Cd levels may induce kidney, liver, or neurological diseases. Cd mainly accumulates in the kidney, causing renal disease in people exposed to moderate to high levels, which leads to the development of end-stage chronic kidney disease or death. The aim of this review is to provide an overview of Cd-induced nephrotoxicity, the mechanisms of Cd damage, and the current treatments used to reduce the toxic effects of Cd exposure.

Biomarker response index in earthworms following chronic exposure to leachate from a closed dumpsite: Behavioral, cytotoxicity and antioxidant system alterations

Leachate, an effluent produced during solid waste decomposition, interacts directly with soil, mainly in dumpsite areas. Studies on terrestrial animal exposure to leachate are, however, lacking. Plants are the most frequently studied organisms, while animal studies, especially earthworms, are limited. Nevertheless, ecotoxicological assessments involving earthworms are crucial due to their role in soil health and ecosystem maintenance, which are paramount in understanding potential terrestrial ecosystem leachate effects. In this context, this study aimed to evaluate behavioral effects, sublethal cytotoxicity and antioxidant system alterations in Eisenia andrei earthworms chronically exposed to leachate from a closed dumpsite. Cytotoxicity was determined by coelomocyte density, viability and cell typing, while antioxidant system alterations were assessed through superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), reduced glutathione (GSH) and metallothionein (MT) determinations. Malondialdehyde (MDA) and protein carbonylation (PTC) levels were also determined as oxidative effect markers. Finally, the Biomarker Response Index (BRI) was assessed, aiming to quantitatively integrate the results of the investigated endpoints and establish a biological health state (BHS) for each leachate concentration. Leachate exposure led to leak responses at concentrations of up to 50%, but attraction at higher concentrations. Decreased cell density (28%) was observed after 48 days and reduced viability (50%), after 14 days of leachate exposure. The observed cell typing changes indicate anti-inflammatory immune system effects. Leachate exposure led to several antioxidant system alterations, increasing SOD (2-6 %), CAT (5-35 %) and GST (5-70 %) activities and GSH (7-37%) and MT (3-67%) levels. Earthworm antioxidant defenses were, however, able to prevent lipid peroxidation, which decreased (11-37%) following leachate exposure to concentrations above 12.5%, and PTC, which increased at 42 days (26%) and reduced at 56 days (12 %). This is the first PTC assessment in leachate-exposed earthworms. The increased carbonylation levels observed after 42 days alongside MDA decreases highlight the need for further research employing oxidative effect biomarkers other than MDA. Finally, an integrated approach employing the BRI was carried out, revealing mild initial changes evolving to moderate to major effects at the highest leachate exposure concentration, with an effect attenuation detected at the end of the experiment. In this sense, this study brings forth a significant novelty, employing a biomarker previously not assessed in earthworms, demonstrating an oxidative effect, alongside the use of the BRI as an integrative tool for the endpoints applied in this assessment.

Antioxidant system alterations, oxidative, and genotoxic effects in Danio rerio (zebrafish) exposed to leachate from a dumpsite

Water body contamination by leachate originated from dumpsites is a concern for municipal solid waste (MSW) management. In this context, this study aimed to evaluate antioxidant system alterations and oxidative and genotoxic effects in Danio rerio (zebrafish) exposed to leachate from a closed dumpsite. Groups comprising 50 fish were exposed (96 h) to different leachate concentrations (5, 15, 30, and 50%) to evaluate effects on liver and brain superoxide dismutase (SOD), catalase (CAT), and glutathione-S-transferase (GST) activities and reduced glutathione (GSH) and metallothionein (MT) concentrations, as well as malondialdehyde (MDA) and protein carbonylation (PTC) levels. Blood genotoxicity was evaluated by the comet assay. The investigated dumpsite leachate pond presented high chloride concentrations (Cl-; 2288.4 ± 69.5 mg L-1) and high electrical conductivity (EC; 8434.0 mS cm-1), indicating the presence of leachate. Concerning Danio rerio exposure, higher SOD (37%), CAT (67%), and GST (39%) activities and higher GSH (57%) concentrations were observed in liver following exposure to 50% leachate, while decreased brain GST (42%) activities and GSH (90%) levels were observed at the same leachate concentration. A significant increase in the olive tail moment (OTM; 280%) indicative of genotoxicity in blood was observed. A principal component analysis indicated that increased enzymatic activities and high levels of both GSH and MT were not sufficient to prevent the accumulation of reactive oxygen species, resulting in PTC and genotoxicity. Therefore, leachate exposure causes sublethal Danio rerio effects, altering the antioxidant system, increasing ROS production, and leading to PTC and genotoxicity. The findings demonstrate the need to further develop sublethal level assessments in zebrafish using leachate from different sources to subsidize risk assessments regarding MSW management.

The Role of Zinc on Liver Fibrosis by Modulating ZIP14 Expression Throughout Epigenetic Regulatory Mechanisms

Zinc plays a pivotal role in tissue regeneration and maintenance being as a central cofactor in a plethora of enzymatic activities. Hypozincemia is commonly seen with chronic liver disease and is associated with an increased risk of liver fibrosis development and hepatocellular carcinoma. Previously favorable effects of zinc supplementation on liver fibrosis have been shown. However, the underlying mechanism of this effect is not elucidated. Liver fibrosis was induced in mice by using CCl4 injection, followed by treatment with zinc chloride (ZnCl2) both at fibrotic and sham groups, and their hepatocytes were isolated. Our results showed that the administration of ZnCl2 restored the depleted cytosolic zinc levels in the hepatocytes isolated from the fibrotic group. Also, alpha-smooth muscle actin (αSMA) expression in hepatocytes was decreased, indicating a reversal of the fibrotic process. Notably, ZIP14 expression significantly increased in the fibrotic group following ZnCl2 treatment, whereas in the sham group ZIP14 expression decreased. Chromatin immunoprecipitation (ChIP) experiments revealed an increased binding percentage of Metal-regulatory transcription factor 1 (MTF1) on ZIP14 promoter in the hepatocytes isolated from fibrotic mice compared to the sham group after ZnCl2 administration. In the same group, the binding percentage of the histone deacetylase HDAC4 on ZIP14 promoter decreased. Our results suggest that the ZnCl2 treatment ameliorates liver fibrosis by elevating intracellular zinc levels through MTF1-mediated regulation of ZIP14 expression and the reduction of ZIP14 deacetylation via HDAC4. The restoration of intracellular zinc concentrations and the modulation of ZIP14 expression by zinc orchestrated through MTF1 and HDAC4, appear to be essential determinants of the therapeutic response in hepatic fibrosis. These findings pave the way for potential novel interventions targeting zinc-related pathways for the treatment of liver fibrosis and associated conditions.

Metal profiling in coronary ischemia-reperfusion injury: Implications for KEAP1/NRF2 regulated redox signaling

Coronary ischemia-reperfusion (IR) injury results from a blockage of blood supply to the heart followed by restoration of perfusion, leading to oxidative stress induced pathological processes. Nuclear factor erythroid 2-related factor 2 (NRF2), a master antioxidant transcription factor, plays a key role in regulating redox signaling. Over the past decades, the field of metallomics has provided novel insights into the mechanism of pro-oxidant and antioxidant pathological processes. Both redox-active (e.g. Fe and Cu) and redox-inert (e.g. Zn and Mg) metals play unique roles in establishing redox balance under IR injury. Notably, Zn protects against oxidative stress in coronary IR injury by serving as a cofactor of antioxidant enzymes such as superoxide dismutase [Cu-Zn] (SOD1) and proteins such as metallothionein (MT) and KEAP1/NRF2 mediated antioxidant defenses. An increase in labile Zn2+ inhibits proteasomal degradation and ubiquitination of NRF2 by modifying KEAP1 and glycogen synthase kinase 3β (GSK3β) conformations. Fe and Cu catalyse the formation of reactive oxygen species via the Fenton reaction and also serve as cofactors of antioxidant enzymes and can activate NRF2 antioxidant signaling. We review the evidence that Zn and redox-active metals Fe and Cu affect redox signaling in coronary cells during IR and the mechanisms by which oxidative stress influences cellular metal content. In view of the unique double-edged characteristics of metals, we aim to bridge the role of metals and NRF2 regulated redox signaling to antioxidant defenses in IR injury, with a long-term aim of informing the design and application of novel therapeutics.

From zinc homeostasis to disease progression: Unveiling the neurodegenerative puzzle

Zinc is a crucial trace element in the human body, playing a role in various physiological processes such as oxidative stress, neurotransmission, protein synthesis, and DNA repair. The zinc transporters (ZnTs) family members are responsible for exporting intracellular zinc, while Zrt- and Irt-like proteins (ZIPs) are involved in importing extracellular zinc. These processes are essential for maintaining cellular zinc homeostasis. Imbalances in zinc metabolism have been linked to the development of neurodegenerative diseases. Disruptions in zinc levels can impact the survival and activity of neurons, thereby contributing to the progression of neurodegenerative diseases through mechanisms like cell apoptosis regulation, protein phase separation, ferroptosis, oxidative stress, and neuroinflammation. Therefore, conducting a systematic review of the regulatory network of zinc and investigating the relationship between zinc dysmetabolism and neurodegenerative diseases can enhance our understanding of the pathogenesis of these diseases. Additionally, it may offer new insights and approaches for the treatment of neurodegenerative diseases.

Combined impact of elevated temperature and zinc oxide nanoparticles on physiological stress and recovery responses of Scylla serrata

Global climate change is the major cause behind unexpected fluctuations in temperature. In recent years, application of nanotechnology also has become widespread and nanomaterials are constantly being released into aquatic environments, posing a potential risk to various organisms and ecosystems. The lack of detailed understanding of how multiple stressors work, and how they differ from single stressors, impede to assess their combined effect on aquatic organisms and ecosystems. The prime aim of the current investigation is to decipher the toxicity of ZnO-NP after simultaneous exposure to a global environmental stressor, elevated temperature for 14 days, followed by a 7 days recovery period, on the eco-physiological responses of mud crab Scylla serrata collected from Sundarbans. Physiological energetics such as ingestion, assimilation, absorption, respiration, and excretion rates were measured to determine the Scope for growth (SfG). Additionally, we assessed various biomarkers from different levels of biological organisation (antioxidant, detoxification defence mechanisms, and lipid peroxidation levels) of the species. Combined stress attenuated the SfG in crabs which deteriorated further in the recovery phase. Oxidative stress also exacerbated under coalesced stress condition. Recovery was not observed in crabs with increased lipid peroxidation level under combined stress conditions. Elevated temperature disturbed the energy budget of crabs as mirrored by diminished energy left for compensatory actions under added metal stress, ultimately sensitizing the animals to ZnO NP pollutants. The current results advocate future ocean temperature to aggravate the impact of metal NP pollution and induce oxidative damage in S. serrata.

Metallothionein 3 promotes osteoclast differentiation and survival by regulating the intracellular Zn2+ concentration and NRF2 pathway

In osteoclastogenesis, the metabolism of metal ions plays an essential role in controlling reactive oxygen species (ROS) production, mitochondrial biogenesis, and survival, and differentiation. However, the mechanism regulating metal ions during osteoclast differentiation remains unclear. The metal-binding protein metallothionein (MT) detoxifies heavy metals, maintains metal ion homeostasis, especially zinc, and manages cellular redox levels. We carried out tests using murine osteoclast precursors to examine the function of MT in osteoclastogenesis and evaluated their potential as targets for future osteoporosis treatments. MT genes were significantly upregulated upon differentiation from osteoclast precursors to mature osteoclasts in response to receptor activators of nuclear factor-κB (NF-κB) ligand (RANKL) stimulation, and MT3 expression was particularly pronounced in mature osteoclasts among MT genes. The knockdown of MT3 in osteoclast precursors demonstrated a remarkable inhibition of differentiation into mature osteoclasts. In preosteoclasts, MT3 knockdown suppressed the activity of mitogen-activated protein kinase (MAPK) and NF-κB signaling pathways upon RANKL stimulation, leading to affect cell survival through elevated cleaved Caspase 3 and poly (ADP-ribose) polymerase (PARP) levels. Additionally, ROS levels were decreased, and nuclear factor erythroid 2-related factor 2 (NRF2) (a suppressor of ROS) and the downstream antioxidant proteins, such as catalase (CAT) and heme oxygenase 1 (HO-1), were more highly expressed in the MT3 preosteoclast knockdowns. mitochondrial ROS, which is involved in mitochondrial biogenesis and the production of reactive oxygen species, were similarly decreased because cAMP response element-binding (CREB) and peroxisome proliferator-activated receptor γ coactivator 1β (PGC-1β) were less activated due to MT3 depletion. Thus, by modulating ROS through the NRF2 pathway, MT3 plays a crucial role in regulating osteoclast differentiation and survival, acting as a metabolic modulator of intracellular zinc ions.

Chronic metabolic stress drives developmental programs and loss of tissue functions in non-transformed liver that mirror tumor states and stratify survival

Under chronic stress, cells must balance competing demands between cellular survival and tissue function. In metabolic dysfunction-associated steatotic liver disease (MASLD, formerly NAFLD/NASH), hepatocytes cooperate with structural and immune cells to perform crucial metabolic, synthetic, and detoxification functions despite nutrient imbalances. While prior work has emphasized stress-induced drivers of cell death, the dynamic adaptations of surviving cells and their functional repercussions remain unclear. Namely, we do not know which pathways and programs define cellular responses, what regulatory factors mediate (mal)adaptations, and how this aberrant activity connects to tissue-scale dysfunction and long-term disease outcomes. Here, by applying longitudinal single-cell multi -omics to a mouse model of chronic metabolic stress and extending to human cohorts, we show that stress drives survival-linked tradeoffs and metabolic rewiring, manifesting as shifts towards development-associated states in non-transformed hepatocytes with accompanying decreases in their professional functionality. Diet-induced adaptations occur significantly prior to tumorigenesis but parallel tumorigenesis-induced phenotypes and predict worsened human cancer survival. Through the development of a multi -omic computational gene regulatory inference framework and human in vitro and mouse in vivo genetic perturbations, we validate transcriptional (RELB, SOX4) and metabolic (HMGCS2) mediators that co-regulate and couple the balance between developmental state and hepatocyte functional identity programming. Our work defines cellular features of liver adaptation to chronic stress as well as their links to long-term disease outcomes and cancer hallmarks, unifying diverse axes of cellular dysfunction around core causal mechanisms.

Protective potential of naringenin and its nanoformulations in redox mechanisms of injury and disease

Increasing evidence suggests that elevated intracellular levels of reactive oxygen species (ROS) play a significant role in the pathogenesis of many diseases. Increased intracellular levels of ROS can lead to the oxidation of lipids, DNA, and proteins, contributing to cellular damage. Hence, the maintenance of redox hemostasis is essential. Naringenin (NAR) is a flavonoid included in the flavanones subcategory. Various pharmacological actions have been ascribable to this phytochemical composition, including antioxidant, anti-inflammatory, antibacterial, antiviral, antitumor, antiadipogenic, neuro-, and cardio-protective activities. This review focused on the underlying mechanism responsible for the antioxidative stress properties of NAR and its' nanoformulations. Several lines of in vitro and in vivo investigations suggest the effects of NAR and its nanoformulation on their target cells via modulating signaling pathways. These nanoformulations include nanoemulsion, nanocarriers, solid lipid nanoparticles (SLN), and nanomicelle. This review also highlights several beneficial health effects of NAR nanoformulations on human diseases including brain disorders, cancer, rheumatoid arthritis, and small intestine injuries. Employing nanoformulation can improve the pharmacokinetic properties of NAR and consequently efficiency by reducing its limitations, such as low bioavailability. The protective effects of NAR and its' nanoformulations against oxidative stress may be linked to the modulation of Nrf2-heme oxygenase-1, NO/cGMP/potassium channel, COX-2, NF-κB, AMPK/SIRT3, PI3K/Akt/mTOR, BDNF, NOX, and LOX-1 pathways. Understanding the mechanism behind the protective effects of NAR can facilitate drug development for the treatment of oxidative stress-related disorders.

Protective potential of thymoquinone against cadmium, arsenic, and lead toxicity: A short review with emphasis on oxidative pathways

Heavy metals are among the most important environmental pollutions used in various industries. Their extensive use has increased human susceptibility to different chronic diseases. Toxic metal exposure, especially cadmium, arsenic, and lead, causes oxidative damages, mitochondrial dysfunction, and genetic and epigenetic modifications. Meanwhile, thymoquinone (TQ) is an effective component of Nigella sativa oil that plays an important role in preventing the destructive effects of heavy metals. The present review discusses how TQ can protect various tissues against oxidative damage of heavy metals. This review is based on the research reported about the protective effects of TQ in the toxicity of heavy metals, approximately the last 10 years (2010-2021). Scientific databases, including Scopus, Web of Science, and PubMed, were searched using the following keywords either alone or in combination: cadmium, arsenic, lead, TQ, and oxidative stress. TQ, as a potent antioxidant, can distribute to cellular compartments and prevent oxidative damage of toxic metals. However, depending on the type of toxic metal and the carrier system used to release TQ in biological systems, its therapeutic dosage range may be varied.

Zinc and α-tocopherol protect the antral follicles and endogenous antioxidants of female albino rats (Rattus norvegicus) against lead toxicity

BACKGROUND

Lead impairs female reproductive health because it can induce oxidative stress. Zinc as an antioxidant produces an enzyme system that helps neutralize free radicals. α-Tocopherol has an antagonistic effect that reduces oxidative stress. This study aimed to demonstrate the effects of zinc (Zn) and α-tocopherol on the ovarian endogenous antioxidants and antral follicles of albino rats (Rattus norvegicus) exposed to lead acetate (Pb(C2H3O2)2).

METHODS

Twenty-five female Wistar rats were divided into five groups, namely groups K (control), P0, P1, P2, and P3. Following exposure and treatment for 21 days with different combinations, the albino rats were necropsied, and their ovaries were removed for subsequent histopathological preparations and endogenous antioxidant analysis. Observations were made on the ovary, including an antral follicle count and diameter calculations. Analysis of the superoxide dismutase (SOD) levels (560 nm wavelength) and malondialdehyde MDA-TBA (532 nm wavelength) were performed by a spectrophotometer. The data were analyzed using a one-way ANOVA and least significant difference (LSD) test with the SPSS V24 software.

RESULTS

The highest SOD enzyme expression in the albino rat ovaries was in P0 (17.23 ± 5.34), and the lowest was in P3 (4.21 ± 0.76). The lowest MDA level was observed in the control group (K) and P3 compared to the other groups. The highest average antral follicle count and diameter were found in the albino rats exposed to 1.5 mg/kg BW lead acetate, and treated with 0.54 mg/kg BW zinc sulfate and 100 mg/kg BW α-tocopherol (group P3) compared to the other groups. The mechanisms of action of zinc and α-tocopherol work synergistically to decrease free radicals and ovarian damage.

CONCLUSION

The results showed that a combination of 0.54 mg/kg BW zinc (Zn) and 100 mg/kg BW α-tocopherol can maintain the number and diameter of the antral follicles and reduce ovarian SOD expression and MDA levels in albino rats exposed to lead acetate.

The two-stage molecular scenery of SARS-CoV-2 infection with implications to disease severity: An in-silico quest

Introduction

The two-stage molecular profile of the progression of SARS-CoV-2 (SCOV2) infection is explored in terms of five key biological/clinical questions: (a) does SCOV2 exhibits a two-stage infection profile? (b) SARS-CoV-1 (SCOV1) vs. SCOV2: do they differ? (c) does and how SCOV2 differs from Influenza/INFL infection? (d) does low viral-load and (e) does COVID-19 early host response relate to the two-stage SCOV2 infection profile? We provide positive answers to the above questions by analyzing the time-series gene-expression profiles of preserved cell-lines infected with SCOV1/2 or, the gene-expression profiles of infected individuals with different viral-loads levels and different host-response phenotypes.

Methods

Our analytical methodology follows an in-silico quest organized around an elaborate multi-step analysis pipeline including: (a) utilization of fifteen gene-expression datasets from NCBI's gene expression omnibus/GEO repository; (b) thorough designation of SCOV1/2 and INFL progression stages and COVID-19 phenotypes; (c) identification of differentially expressed genes (DEGs) and enriched biological processes and pathways that contrast and differentiate between different infection stages and phenotypes; (d) employment of a graph-based clustering process for the induction of coherent groups of networked genes as the representative core molecular fingerprints that characterize the different SCOV2 progression stages and the different COVID-19 phenotypes. In addition, relying on a sensibly selected set of induced fingerprint genes and following a Machine Learning approach, we devised and assessed the performance of different classifier models for the differentiation of acute respiratory illness/ARI caused by SCOV2 or other infections (diagnostic classifiers), as well as for the prediction of COVID-19 disease severity (prognostic classifiers), with quite encouraging results.

Results

The central finding of our experiments demonstrates the down-regulation of type-I interferon genes (IFN-1), interferon induced genes (ISGs) and fundamental innate immune and defense biological processes and molecular pathways during the early SCOV2 infection stages, with the inverse to hold during the later ones. It is highlighted that upregulation of these genes and pathways early after infection may prove beneficial in preventing subsequent uncontrolled hyperinflammatory and potentially lethal events.

Discussion

The basic aim of our study was to utilize in an intuitive, efficient and productive way the most relevant and state-of-the-art bioinformatics methods to reveal the core molecular mechanisms which govern the progression of SCOV2 infection and the different COVID-19 phenotypes.

Essential and non-essential elements in tuna and billfish around the world: Distribution patterns and influencing factors

Tuna and billfish are widely distributed in oceans worldwide. Their survival is relied on a decent share of essential and non-essential elements. We conducted a comprehensive evaluation of essential and non-essential elements in livers of tuna and billfish collected from global oceans. The individual element consistently shown similar orders of magnitude in both tuna and billfish, with essential elements generally being 1-3 orders of magnitude higher than non-essential elements. Various physicochemical properties and behaviors contributed to four distinct clusters of these elements. Also, element distribution pattern indicated the presence of four sample groups based on regions and categories. Nine elements served as characteristic indicators. Among them, fish category was the most important influencing factor. Hg, Fe, Tl, Co, and Se were influenced by body size, trophic level, and feeding habits. Ni was influenced by sampling regions, while Mg, Mn and As were influenced by body size and local primary production.

Short C-terminal Musashi-1 proteins regulate pluripotency states in embryonic stem cells

The RNA-binding protein Musashi-1 (MSI1) regulates the proliferation and differentiation of adult stem cells. However, its role in embryonic stem cells (ESCs) and early embryonic development remains poorly understood. Here, we report the presence of short C-terminal MSI1 (MSI1-C) proteins in early mouse embryos and mouse ESCs, but not in human ESCs, under conventional culture conditions. In mouse embryos and mESCs, deletion of MSI1-C together with full-length MSI1 causes early embryonic developmental arrest and pluripotency dissolution. MSI1-C is induced upon naive induction and facilitates hESC naive pluripotency acquisition, elevating the pluripotency of primed hESCs toward a formative-like state. MSI1-C proteins are nuclear localized and bind to RNAs involved in DNA-damage repair (including MLH1, BRCA1, and MSH2), conferring on hESCs better survival in human-mouse interspecies cell competition and prolonged ability to form blastoids. This study identifies MSI1-C as an essential regulator in ESC pluripotency states and early embryonic development.

Contaminant Metals and Cardiovascular Health

A growing body of research has begun to link exposure to environmental contaminants, such as heavy metals, with a variety of negative health outcomes. In this paper, we sought to review the current research describing the impact of certain common contaminant metals on cardiovascular (CV) health. We reviewed ten metals: lead, barium, nickel, chromium, cadmium, arsenic, mercury, selenium, zinc, and copper. After a literature review, we briefly summarized the routes of environmental exposure, pathophysiological mechanisms, CV health impacts, and exposure prevention and/or mitigation strategies for each metal. The resulting article discloses a broad spectrum of pathological significance, from relatively benign substances with little to no described effects on CV health, such as chromium and selenium, to substances with a wide-ranging and relatively severe spectrum of CV pathologies, such as arsenic, cadmium, and lead. It is our hope that this article will provide clinicians with a practical overview of the impact of these common environmental contaminants on CV health as well as highlight areas that require further investigation to better understand how these metals impact the incidence and progression of CV diseases.

Probing cerebral malaria inflammation in 3D human brain microvessels

Sequestration of Plasmodium falciparum-infected erythrocytes (IEs) in the brain microcirculation is a hallmark of cerebral malaria (CM), which leads to endothelial activation, brain swelling, and death. Here, we probed CM inflammation in a perfusable 3D human brain microvessel model. 3D brain microvessels supported in vivo-like capacities for parasite binding and maturation in situ, leading to a distinct inflammatory response from the pro-inflammatory cytokine tumor necrosis factor α (TNF-α). By combining transcriptional analysis, imaging, and leukocyte perfusion, we showed that whereas TNF-α promotes a reversible inflammatory phenotype with widespread leukocyte recruitment, parasites induce unique stress response pathways and cause localized cell adhesivity changes, focal endothelial disruptions, and apoptosis. Furthermore, parasites modified the temporal kinetics of the TNF transcriptional response, suggesting augmented inflammatory damage with the two sequential stimuli. Our findings offer mechanistic insights into CM biology in a 3D brain microvessel mimetic platform and suggest that multiple events intersect to promote brain barrier inflammation in CM.

Antiviral activity of zinc against hepatitis viruses: current status and future prospects

Viral hepatitis is a major public health concern globally. World health organization aims at eliminating viral hepatitis as a public health threat by 2030. Among the hepatitis causing viruses, hepatitis B and C are primarily transmitted via contaminated blood. Hepatitis A and E, which gets transmitted primarily via the feco-oral route, are the leading cause of acute viral hepatitis. Although vaccines are available against some of these viruses, new cases continue to be reported. There is an urgent need to devise a potent yet economical antiviral strategy against the hepatitis-causing viruses (denoted as hepatitis viruses) for achieving global elimination of viral hepatitis. Although zinc was known to mankind for a long time (since before Christ era), it was identified as an element in 1746 and its importance for human health was discovered in 1963 by the pioneering work of Dr. Ananda S. Prasad. A series of follow up studies involving zinc supplementation as a therapy demonstrated zinc as an essential element for humans, leading to establishment of a recommended dietary allowance (RDA) of 15 milligram zinc [United States RDA for zinc]. Being an essential component of many cellular enzymes and transcription factors, zinc is vital for growth and homeostasis of most living organisms, including human. Importantly, several studies indicate potent antiviral activity of zinc. Multiple studies have demonstrated antiviral activity of zinc against viruses that cause hepatitis. This article provides a comprehensive overview of the findings on antiviral activity of zinc against hepatitis viruses, discusses the mechanisms underlying the antiviral properties of zinc and summarizes the prospects of harnessing the therapeutic benefit of zinc supplementation therapy in reducing the disease burden due to viral hepatitis.

Free zinc ions, as a major factor of ZnONP toxicity, disrupts free radical homeostasis in CCRF-CEM cells

Nanotechnology has become a ubiquitous part of our everyday life. Besides the already-known nanoparticles (NPs), plenty of new nanomaterials are being synthesized every day. Here, we explain the mechanism of the zinc oxide nanoparticles (ZnONPs) cytotoxicity in a cellular model of acute lymphoblastic leukaemia (CCRF-CEM). To do so, we investigated both possible hypotheses about the ZnONPs mechanism of toxicity: a free zinc ions release and/or reactive oxygen species (ROS) generation. Presented here results show that: Our results support the hypothesis that the mechanism of ZnONPs cytotoxicity is based on the release of free zinc ions. Nevertheless, both previously quoted hypotheses incompletely described the mechanism of action of ZnONPs. In this paper, we show that the mechanism of cytotoxicity of ZnONPs is based on the induction of reductive stress in CCRF-CEM cells, which is caused by free zinc ions released from ZnONPs. Therefore, the increase of oxidative stress markers is most likely a secondary response of the cells towards the Zn2+. These results provide a crucial expansion of the zinc ion hypothesis and thus explain the biphasic cellular response of CCRF-CEM cells treated with ZnONPs.

Copper induces neuron-sparing, ferredoxin 1-independent astrocyte toxicity mediated by oxidative stress

Copper is an essential enzyme cofactor in oxidative metabolism, anti-oxidant defenses, and neurotransmitter synthesis. However, intracellular copper, when improperly buffered, can also lead to cell death. Given the growing interest in the use of copper in the presence of the ionophore elesclomol (CuES) for the treatment of gliomas, we investigated the effect of this compound on the surround parenchyma-namely neurons and astrocytes in vitro. Here, we show that astrocytes were highly sensitive to CuES toxicity while neurons were surprisingly resistant, a vulnerability profile that is opposite of what has been described for zinc and other toxins. Bolstering these findings, a human astrocytic cell line was similarly sensitive to CuES. Modifications of cellular metabolic pathways implicated in cuproptosis, a form of copper-regulated cell death, such as inhibition of mitochondrial respiration or knock-down of ferredoxin 1 (FDX1), did not block CuES toxicity to astrocytes. CuES toxicity was also unaffected by inhibitors of apoptosis, necrosis or ferroptosis. However, we did detect the presence of lipid peroxidation products in CuES-treated astrocytes, indicating that oxidative stress is a mediator of CuES-induced glial toxicity. Indeed, treatment with anti-oxidants mitigated CuES-induced cell death in astrocytes indicating that oxidative stress is a mediator of CuES-induced glial toxicity. Lastly, prior induction of metallothioneins 1 and 2 in astrocytes with zinc plus pyrithione was strikingly protective against CuES toxicity. As neurons express high levels of metallothioneins basally, these results may partially account for their resistance to CuES toxicity. These results demonstrate a unique toxic response to copper in glial cells which contrasts with the cell selectivity profile of zinc, another biologically relevant metal.

Cu(I) binds to Zn7-MT2 via two parallel pathways

Metallothionein proteins are essential for Cu(I) and Zn(II) homeostasis as well as heavy metal detoxification. The metallation properties of MT2 are of great interest due to their wide patterns of expression and correlation with multiple diseases including cancers, neurological disorders, and respiratory diseases. Use of isotopically pure 63Cu(I) and 68Zn(II) eliminates the complexity of the Cu, Zn-MT2 mass spectral peaks due to significant overlap of naturally abundant isotopes. This allows for the resolution of the precise Cu(I) and Zn(II) stoichiometries when both Cu(I) and Zn(II) are bound to MT2 at physiological pH as expected in vivo. Exact Cu: Zn ratios were determined from mass spectral simulations carried out for every point in the titration. We report that Cu(I) metallation of Zn7-MT2 can only be understood in terms of two pathways occurring in parallel with pathway ① resulting in Cu5Zn5-MT2 and Cu9Zn3-MT2. Pathway ② results in Cu6Zn4-MT2 and Cu10Zn2-MT2, which are the major products of the reaction. From the electrospray ionization (ESI)-mass spectral data we report a series of formation constants (KF) for species starting from Zn7-MT2 up to Cu11Zn2-MT2. Room temperature phosphorescence and circular dichroism (CD) spectra were measured in parallel with the ESI-mass spectrometry data allowing for the assignment of specific species to specific spectral bands. Through analysis of the CD spectral bands, we propose that Cu(I) binds to the β domain first to form a Cu5Zn1 cluster or Cu6 cluster with emission at 670 and 750 nm, respectively, leaving the Zn4 cluster in the α domain.

Metallothionein-3: 63 Cu(I) binds to human 68 Zn7 -βα MT3 with no preference for Cu4 -β cluster formation

Human metallothioneins (MTs) are involved in binding the essential elements, Cu(I) and Zn(II), and the toxic element, Cd(II), in metal-thiolate clusters using 20 reduced cysteines. The brain-specific MT3 binds a mixture of Cu(I) and Zn(II) in vivo. Its metallation properties are critically important because of potential connections between Cu, Zn and neurodegenerative diseases. We report that the use of isotopically pure 63 Cu(I) and 68 Zn(II) greatly enhances the element resolution in the ESI-mass spectral data revealing species with differing Cu:Zn ratios but the same total number of metals. Room temperature phosphorescence and circular dichroism spectral data measured in parallel with ESI-mass spectral data identified the presence of specific Cu(I)-thiolate clusters in the presence of Zn(II). A series of Cu(I)-thiolate clusters form following Cu(I) addition to apo MT3: the two main clusters that form are a Cu6 cluster in the β domain followed by a Cu4 cluster in the α domain. 63 Cu(I) addition to 68 Zn7 -MT3 results in multiple species, including clustered Cu5 Zn5 -MT3 and Cu9 Zn3 -MT3. We assign the domain location of the metals for Cu5 Zn5 -MT3 as a Cu5 Zn1 -β cluster and a Zn4 -α cluster and for Cu9 Zn3 -MT3 as a Cu6 -β cluster and a Cu3 Zn3 -α cluster. While many reports of the average MT3 metal content exist, determining the exact Cu,Zn stoichiometry has proven very difficult even with native ESI-MS. The work in this paper solves the ambiguity introduced by the overlap of the naturally abundant Cu(I) and Zn(II) isotopes. Contrary to other reports, there is no indication of a major fraction of Cu4 -β-Znn -α-MT3 forming.

Toxicological and pharmacokinetic properties of sucralose-6-acetate and its parent sucralose: in vitro screening assays

The purpose of this study was to determine the toxicological and pharmacokinetic properties of sucralose-6-acetate, a structural analog of the artificial sweetener sucralose. Sucralose-6-acetate is an intermediate and impurity in the manufacture of sucralose, and recent commercial sucralose samples were found to contain up to 0.67% sucralose-6-acetate. Studies in a rodent model found that sucralose-6-acetate is also present in fecal samples with levels up to 10% relative to sucralose which suggest that sucralose is also acetylated in the intestines. A MultiFlow® assay, a high-throughput genotoxicity screening tool, and a micronucleus (MN) test that detects cytogenetic damage both indicated that sucralose-6-acetate is genotoxic. The mechanism of action was classified as clastogenic (produces DNA strand breaks) using the MultiFlow® assay. The amount of sucralose-6-acetate in a single daily sucralose-sweetened drink might far exceed the threshold of toxicological concern for genotoxicity (TTCgenotox) of 0.15 µg/person/day. The RepliGut® System was employed to expose human intestinal epithelium to sucralose-6-acetate and sucralose, and an RNA-seq analysis was performed to determine gene expression induced by these exposures. Sucralose-6-acetate significantly increased the expression of genes associated with inflammation, oxidative stress, and cancer with greatest expression for the metallothionein 1 G gene (MT1G). Measurements of transepithelial electrical resistance (TEER) and permeability in human transverse colon epithelium indicated that sucralose-6-acetate and sucralose both impaired intestinal barrier integrity. Sucralose-6-acetate also inhibited two members of the cytochrome P450 family (CYP1A2 and CYP2C19). Overall, the toxicological and pharmacokinetic findings for sucralose-6-acetate raise significant health concerns regarding the safety and regulatory status of sucralose itself.

Metallothionein Cup1 attenuates nitrosative stress in the yeast Saccharomyces cerevisiae

Metallothionein (MT), which is a small metal-binding protein with cysteine-rich motifs, functions in the detoxification of heavy metals in a variety of organisms. Even though previous studies suggest that MT is involved in the tolerance mechanisms against nitrosative stress induced by toxic levels of nitric oxide (NO) in mammalian cells, the physiological functions of MT in relation to NO have not been fully understood. In this study, we analyzed the functions of MT in nitrosative stress tolerance in the yeast Saccharomyces cerevisiae. Our phenotypic analyses showed that deletion or overexpression of the MT-encoding gene, CUP1, led to higher sensitivity or tolerance to nitrosative stress in S. cerevisiae cells, respectively. We further examined whether the yeast MT Cup1 in the cell-free lysate scavenges NO. These results showed that the cell-free lysate containing a higher level of Cup1 degraded NO more efficiently. On the other hand, the transcription level of CUP1 was not affected by nitrosative stress treatment. Our findings suggest that the yeast MT Cup1 contributes to nitrosative stress tolerance, possibly as a constitutive rather than an inducible defense mechanism.

Genome-wide screening in pluripotent cells identifies Mtf1 as a suppressor of mutant huntingtin toxicity

Huntington's disease (HD) is a neurodegenerative disorder caused by CAG-repeat expansions in the huntingtin (HTT) gene. The resulting mutant HTT (mHTT) protein induces toxicity and cell death via multiple mechanisms and no effective therapy is available. Here, we employ a genome-wide screening in pluripotent mouse embryonic stem cells (ESCs) to identify suppressors of mHTT toxicity. Among the identified suppressors, linked to HD-associated processes, we focus on Metal response element binding transcription factor 1 (Mtf1). Forced expression of Mtf1 counteracts cell death and oxidative stress caused by mHTT in mouse ESCs and in human neuronal precursor cells. In zebrafish, Mtf1 reduces malformations and apoptosis induced by mHTT. In R6/2 mice, Mtf1 ablates motor defects and reduces mHTT aggregates and oxidative stress. Our screening strategy enables a quick in vitro identification of promising suppressor genes and their validation in vivo, and it can be applied to other monogenic diseases.

Combined toxic effects of cadmium and environmental microplastics in Aphanius fasciatus (Pisces, Cyprinodontidae)

Microplastics (MPs), plastic particles smaller than 5 mm in diameter, have received extensive attention as new environmental pollutants with still unexplored potential ecological risks. The main objective of the present study is to see if the concomitant exposure to MPs and Cd is more toxic than that to MPs or Cd separately in Aphanius fasciatus. Immature female were exposed to Cd and/or MPs for 21 days, and the subsequent effects were monitored by a combination of biochemical, histological and molecular toxicity markers. Exposure to Cd, but not to MPs, increased metallothioneins content and mRNA levels of the metallothioneins gene MTA both in liver and gills. In addition, we observed a significant oxidative stress response at histological, enzymatic (Catalase and Superoxide dismutase), non-enzymatic (proteins sulfhydryl and malondialdehyde) and gene expression levels to both toxicants in both tissues, particularly in gills, but no clear evidence for interaction between the two factors. Our results indicate a major effect of MPs on gills at different organizational levels. Finally, exposure to both MPs and Cd induced spinal deformities, although bone composition was only altered by the latter, whereas MTA mRNA bone levels were only increased realtive to controls in doubly-exposed samples. Interestingly, the simultaneous use of both pollutants produced the same effects as Cd and MPs alone, probably due to reduced bioavailability of this heavy metal.