Effects of iron and copper overload on the human liver: an ultrastructural study

The effect of lipid metabolism on cuproptosis-inducing cancer therapy

Cuproptosis provides a new therapeutic strategy for cancer treatment and is thought to have broad clinical application prospects. Nevertheless, some oncological clinical trials have yet to demonstrate favorable outcomes, highlighting the need for further research into the molecular mechanisms underlying cuproptosis in tumors. Cuproptosis primarily hinges on the intracellular accumulation of copper, with lipid metabolism exerting a profound influence on its course. The interaction between copper metabolism and lipid metabolism is closely related to cuproptosis. Copper imbalance can affect mitochondrial respiration and lipid metabolism changes, while lipid accumulation can promote copper uptake and absorption, and inhibit cuproptosis induced by copper. Anomalies in lipid metabolism can disrupt copper homeostasis within cells, potentially triggering cuproptosis. The interaction between cuproptosis and lipid metabolism regulates the occurrence, development, metastasis, chemotherapy drug resistance, and tumor immunity of cancer. Cuproptosis is a promising new target for cancer treatment. However, the influence of lipid metabolism and other factors should be taken into consideration. This review provides a brief overview of the characteristics of the interaction between cuproptosis and lipid metabolism in cancer and analyses potential strategies of applying cuproptosis for cancer treatment.

Iron deficiency and supplementation in heart failure

Non-anaemic iron deficiency (NAID) is a strategic target in cardiovascular medicine because of its association with a range of adverse effects in various conditions. Endeavours to tackle NAID in heart failure have yielded mixed results, exposing knowledge gaps in how best to define 'iron deficiency' and the handling of iron therapies by the body. To address these gaps, we harness the latest understanding of the mechanisms of iron homeostasis outside the erythron and integrate clinical and preclinical lines of evidence. The emerging picture is that current definitions of iron deficiency do not assimilate the multiple influences at play in patients with heart failure and, consequently, fail to identify those with a truly unmet need for iron. Additionally, current iron supplementation therapies benefit only certain patients with heart failure, reflecting differences in the nature of the unmet need for iron and the modifying effects of anaemia and inflammation on the handling of iron therapies by the body. Building on these insights, we identify untapped opportunities in the management of NAID, including the refinement of current approaches and the development of novel strategies. Lessons learned from NAID in cardiovascular disease could ultimately translate into benefits for patients with other chronic conditions such as chronic kidney disease, chronic obstructive pulmonary disease and cancer.

Excess iron intake induced liver injury: The role of gut-liver axis and therapeutic potential

Excessive iron intake is detrimental to human health, especially to the liver, which is the main organ for iron storage. Excessive iron intake can lead to liver injury. The gut-liver axis (GLA) refers to the bidirectional relationship between the gut and its microbiota and the liver, which is a combination of signals generated by dietary, genetic and environmental factors. Excessive iron intake disrupts the GLA at multiple interconnected levels, including the gut microbiota, gut barrier function, and the liver's innate immune system. Excessive iron intake induces gut microbiota dysbiosis, destroys gut barriers, promotes liver exposure to gut microbiota and its derived metabolites, and increases the pro-inflammatory environment of the liver. There is increasing evidence that excess iron intake alters the levels of gut microbiota-derived metabolites such as secondary bile acids (BAs), short-chain fatty acids, indoles, and trimethylamine N-oxide, which play an important role in maintaining homeostasis of the GLA. In addition to iron chelators, antioxidants, and anti-inflammatory agents currently used in iron overload therapy, gut barrier intervention may be a potential target for iron overload therapy. In this paper, we review the relationship between excess iron intake and chronic liver diseases, the regulation of iron homeostasis by the GLA, and focus on the effects of excess iron intake on the GLA. It has been suggested that probiotics, fecal microbiota transfer, farnesoid X receptor agonists, and microRNA may be potential therapeutic targets for iron overload-induced liver injury by protecting gut barrier function.

Impacts of iron on ultrastructural features of NCI-H295R cell line related to steroidogenesis

The current study was intended to evaluate impacts of both iron (Fe) enrichment and overload (in the form of ferrous sulphate heptahydrate, FeSO4.7H2O) on ultrastructural characteristics of human adrenocarcinoma NCI-H295R cell line. Here, the NCI-H295R cells were treated with 0, 3.90, and 1000 µM FeSO4.7H2O, and consequently proceeded for purposes of ultrastructural studies. Micrographs taken under transmission electron microscope (TEM) were investigated from the qualitative and quantitative (unbiased stereological approaches) aspects, and obtained findings were compared among the three groups of the cells. The ultrastructural features related to the steroidogenic process were found to be similar between the untreated and both Fe-exposed cell populations, with conspicuous mitochondria with well-defined lamellar cristae (creating clusters of varying sizes in the regions of increased energy demands) and concentric whorls of smooth endoplasmic reticulum (SER) being the most noticeable characteristics. The precise estimates of the component (volume, surface) fractions of the nucleus, mitochondria, and lipid droplets (LDs), as well as of the nucleus/cytoplasm (N/C) ratio have revealed close similarities (P > 0.05) in all cell groups investigated. Nonetheless, the low concentration of FeSO4.7H2O exhibited beneficial action on ultrastructural organization of the NCI-H295R cells. In effect, these cells were distinguished by mitochondria with smoother surfaces and clearer outlines, higher density of thin, parallel lamellar cristae (deeply extending into the mitochondrial matrix), and more widespread distribution of fine SER tubules as compared to the control ones, all of them suggesting higher level of energy requirements and metabolic activity, and more intensive rate of steroidogenesis. Interestingly, no obvious ultrastructural modifications were observed in the NCI-H295R cells treated with high FeSO4.7H2O concentration. This finding can be linked to either an adaptive ultrastructural machinery of these cells to cope with the adverse effect of the element or to insufficient dose of FeSO4.7H2O (1000 µM) to induce ultrastructural signs of cytotoxicity. Purposefully, the results of the current study complement our previous paper dealing with impacts of FeSO4.7H2O on the NCI-H295R cell viability and steroidogenesis at the molecular level. Hence, they fill a knowledge gap considering structure-function coupling in this cellular model system upon the metal exposure. This integrated approach can enhance our understanding of the cellular responses to Fe enrichment and overload which can be helpful for individuals with reproductive health concerns.

Copper metabolism and hepatocellular carcinoma: current insights

Copper is an essential trace element that acts as a cofactor in various enzyme active sites in the human body. It participates in numerous life activities, including lipid metabolism, energy metabolism, and neurotransmitter synthesis. The proposal of "Cuproptosis" has made copper metabolism-related pathways a research hotspot in the field of tumor therapy, which has attracted great attention. This review discusses the biological processes of copper uptake, transport, and storage in human cells. It highlights the mechanisms by which copper metabolism affects hepatocellular carcinogenesis and metastasis, including autophagy, apoptosis, vascular invasion, cuproptosis, and ferroptosis. Additionally, it summarizes the current clinical applications of copper metabolism-related drugs in antitumor therapy.

Substantial Copper (Cu2+) Uptake by Metakaolin-Based Geopolymer and Its Resistance to Acid Leaching and Ion Exchange

Geopolymers are inorganic, chemically resistant aluminosilicate-based binding agents, which remove hazardous metal ions from exposed aqueous media. However, the removal efficiency of a given metal ion and the potential ion remobilization have to be assessed for individual geopolymers. Therefore, copper ions (Cu²⁺) were removed by a granulated, metakaolin-based geopolymer (GP) in water matrices. Subsequent ion exchange and leaching tests were used to determine the mineralogical and chemical properties as well as the resistance of the Cu²⁺-bearing GPs to corrosive aquatic environments. Experimental results indicate the pH of the reacted solutions to have a significant impact on the Cu²⁺ uptake systematics: the removal efficiency ranged from 34-91% at pH 4.1-5.7 up to ~100% at pH 11.1-12.4. This is equivalent to Cu²⁺ uptake capacities of up to 193 mg/g and 560 mg/g in acidic versus alkaline media. The uptake mechanism was governed by Cu²⁺-substitution for alkalis in exchangeable GP sites and by co-precipitation of gerhardtite (Cu₂(NO₃)(OH)₃) or tenorite (CuO) and spertiniite (Cu(OH)₂). All Cu-GPs showed excellent resistance to ion exchange (Cu²⁺ release: 0-2.4%) and acid leaching (Cu²⁺ release: 0.2-0.7%), suggesting that tailored GPs have a high potential to immobilize Cu²⁺ ions from aquatic media.

Exposure to copper activates mitophagy and endoplasmic reticulum stress-mediated apoptosis in chicken (Gallus gallus) cerebrum

A large amount of copper (Cu) used in production activities can lead to the enrichment of Cu in the environment, which can cause toxicity to animals. However, the toxicity mechanism of Cu on the cerebrum is still uncertain. Hence, a total of 240 chickens were separated into four groups in this study to reveal the potential connection between mitophagy and endoplasmic reticulum (ER) stress-mediated apoptosis in the chicken cerebrum in the case of excess Cu exposure. The cu exposure situation was simulated by diets containing various levels of copper (11 mg/kg, control group; 110 mg/kg, group I; 220 mg/kg, group II and 330 mg/kg, group III) for 49 days. The results of histology showed that vacuolar degeneration was observed in the treated groups, and the mitochondria swell and autophagosomes formation were found under excess Cu treatment. Additionally, the expression of mitophagy (PINK1, Parkin, LC3I, LC3II and p62) and ER stress (GRP78, PERK, ATF6, IRE1α, XBP1, CHOP, and JNK) indexes were significantly upregulated under excess Cu exposure. Furthermore, the mRNA and protein expression of Bcl-2 were decreased, while Bak1, Bax, Caspase12, and Caspase3 were increased compared to the control group. In summary, this study demonstrated that an overdose of Cu could induce mitophagy and ER stress-mediated apoptosis in the chicken cerebrum. These findings revealed an important potential connection between Cu toxicity and cerebrum damage, which provided a new insight into Cu neurotoxicity.

Analyzing the Therapeutic Efficacy of Bis-Choline-Tetrathiomolybdate in the Atp7b-/- Copper Overload Mouse Model

Bis-choline-tetrathiomolybdate, introduced as WTX101 (now known as ALXN1840), is a first-in-class copper-protein-binding agent for oral therapy of Wilson’s disease. In contrast to other decoppering agents such as trientine or D-penicillamine it acts by forming a tripartite complex with copper and albumin, thereby detoxifying excess liver and blood copper through biliary excretion. Preclinical animal experimentation with this drug was typically done with the alternative ammonium salt of tetrathiomolybdate, which is expected to have identical properties in terms of copper binding. Here, we comparatively analyzed the therapeutic efficacy of ALXN1840, D-penicillamine and trientine in lowering hepatic copper content in Atp7b^−/− mouse. Liver specimens were subjected to laser ablation inductively conductively plasma mass spectrometry and electron microscopic analysis. We found that ALXN1840 caused a massive increase of hepatic copper and molybdenum during early stages of therapy. Prolonged treatment with ALXN1840 reduced hepatic copper to an extent that was similar to that observed after administration of D-penicillamine and trientine. Electron microscopic analysis showed a significant increase of lysosomal electron-dense particles in the liver confirming the proposed excretory pathway of ALXN1840. Ultrastructural analysis of mice treated with dosages comparable to the bis-choline-tetrathiomolybdate dosage used in an ongoing phase III trial in Wilson’s disease patients, as well as D-penicillamine and trientine, did not show relevant mitochondrial damage. In contrast, a high dose of ALXN1840 applied for four weeks triggered dramatic structural changes in mitochondria, which were notably characterized by the formation of holes with variable sizes. Although these experimental results may not be applicable to patients with Wilson’s disease, the data suggests that ALXN1840 should be administered at low concentrations to prevent mitochondrial dysfunction and overload of hepatic excretory pathways.

A State-of-the-Art Review on Innovative Geopolymer Composites Designed for Water and Wastewater Treatment

There is nothing more fundamental than clean potable water for living beings next to air. On the other hand, wastewater management is cropping up as a challenging task day-by-day due to lots of new additions of novel pollutants as well as the development of infrastructures and regulations that could not maintain its pace with the burgeoning escalation of populace and urbanizations. Therefore, momentous approaches must be sought-after to reclaim fresh water from wastewaters in order to address this great societal challenge. One of the routes is to clean wastewater through treatment processes using diverse adsorbents. However, most of them are unsustainable and quite costly e.g. activated carbon adsorbents, etc. Quite recently, innovative, sustainable, durable, affordable, user and eco-benevolent Geopolymer composites have been brought into play to serve the purpose as a pretty novel subject matter since they can be manufactured by a simple process of Geopolymerization at low temperature, lower energy with mitigated carbon footprints and marvellously, exhibit outstanding properties of physical and chemical stability, ion-exchange, dielectric characteristics, etc., with a porous structure and of course lucrative too because of the incorporation of wastes with them, which is in harmony with the goal to transit from linear to circular economy, i.e., "one's waste is the treasure for another". For these reasons, nowadays, this ground-breaking inorganic class of amorphous alumina-silicate materials are drawing the attention of the world researchers for designing them as adsorbents for water and wastewater treatment where the chemical nature and structure of the materials have a great impact on their adsorption competence. The aim of the current most recent state-of-the-art and scientometric review is to comprehend and assess thoroughly the advancements in geo-synthesis, properties and applications of geopolymer composites designed for the elimination of hazardous contaminants viz., heavy metal ions, dyes, etc. The adsorption mechanisms and effects of various environmental conditions on adsorption efficiency are also taken into account for review of the importance of Geopolymers as most recent adsorbents to get rid of the death-defying and toxic pollutants from wastewater with a view to obtaining reclaimed potable and sparkling water for reuse offering to trim down the massive crisis of scarcity of water promoting sustainable water and wastewater treatment for greener environments. The appraisal is made on the performance estimation of Geopolymers for water and wastewater treatment along with the three-dimensional printed components are characterized for mechanical, physical and chemical attributes, permeability and Ammonium (NH4+) ion removal competence of Geopolymer composites as alternative adsorbents for sequestration of an assortment of contaminants during wastewater treatment.

Wilson disease and the differential diagnosis of its hepatic manifestations: a narrative review of clinical, laboratory, and liver histological features

Objective

The goal of the present work is to provide an overview of the differential diagnosis of Wilson disease.

Background

Wilson disease is a rare condition due to copper accumulation primarily in the liver and brain. Although there is no definitive cure, current anti-copper treatments are associated with better outcomes if initiated early and if the diagnosis is made promptly. However, diagnostic delays are frequent and often Wilson disease represents a diagnostic challenge. The diagnosis ultimately relies on a combination of clinical, laboratory and genetic findings, and it is crucial that clinicians list Wilson disease in their differential diagnosis, especially in patients presenting with a hepatocellular pattern of liver injury. Some biochemical and liver histological features of Wilson disease overlap with those of more common conditions including nonalcoholic fatty liver disease, alcohol-associated liver disease, and autoimmune hepatitis. In particular, hepatic steatosis, hepatocyte glycogenated nuclei, ballooning degeneration, and Mallory-Denk bodies are often identified in Wilson disease as well as more common liver diseases. In addition, the natural history of liver damage in Wilson disease and the risk of developing liver cancer are largely understudied.

Methods

We conducted an enlarged review of published papers on Wilson disease focusing on its diagnosis and distinctive clinical and liver pathology features in relation to common non-cholestatic liver diseases with the final goal in aiding clinicians in the diagnostic process of this rare but treatable condition.

Conclusions

Aside from markedly altered copper metabolism, Wilson disease has essentially no pathognomonic features that can distinguish it from more common liver diseases. Clinicians should be aware of this challenge and consider Wilson disease in patients presenting with a hepatocellular pattern of liver injury.

Zinc as a Drug for Wilson's Disease, Non-Alcoholic Liver Disease and COVID-19-Related Liver Injury

Zinc is the second most abundant trace element in the human body, and it plays a fundamental role in human physiology, being an integral component of hundreds of enzymes and transcription factors. The discovery that zinc atoms may compete with copper for their absorption in the gastrointestinal tract let to introduce zinc in the therapy of Wilson's disease, a congenital disorder of copper metabolism characterized by a systemic copper storage. Nowadays, zinc salts are considered one of the best therapeutic approach in patients affected by Wilson's disease. On the basis of the similarities, at histological level, between Wilson's disease and non-alcoholic liver disease, zinc has been successfully introduced in the therapy of non-alcoholic liver disease, with positive effects both on insulin resistance and oxidative stress. Recently, zinc deficiency has been indicated as a possible factor responsible for the susceptibility of elderly patients to undergo infection by SARS-CoV-2, the coronavirus responsible for the COVID-19 pandemic. Here, we present the data correlating zinc deficiency with the insurgence and progression of Covid-19 with low zinc levels associated with severe disease states. Finally, the relevance of zinc supplementation in aged people at risk for SARS-CoV-2 is underlined, with the aim that the zinc-based drug, classically used in the treatment of copper overload, might be recorded as one of the tools reducing the mortality of COVID-19, particularly in elderly people.

The Role of Magnesium in Pregnancy and in Fetal Programming of Adult Diseases

Magnesium is an essential trace metal and a necessary factor for multiple biochemical functions in humans. Its role in biology is fundamental in over 600 enzymatic reactions implicated in protein synthesis, mitochondrial functions, neuromuscular activity, bone formation, and immune system competence. Magnesium status is relevant in fetal development during gestation and in the newborn growth during the perinatal period. Moreover, magnesium is able to influence fetal programming and disease presentation in childhood or adulthood. The aim of this review is to focus on this metal homeostasis, analyzing its normal values, the causes of hypomagnesemia, the interaction with drugs and other conditions, and the diseases associated with magnesium value alteration during pregnancy, in order to study its role in fetal programming of adult diseases. The data here reported clearly indicated the existence of a connection between magnesium status and human pathology starting from intrauterine life and extending into childhood and adulthood.

Association between Hypomagnesemia, COVID-19, Respiratory Tract and Lung Disease

The complexity of COVID-19 is also related to the multiple molecular pathways triggered by SARS-CoV-2, which is able to cause type I pneumocyte death, trigger intravascular coagulation, interfere with the renin-angiotensin system, dysregulate iron metabolism, ending with the insurgence of a cytokine storm which may lead to death. Old adults with obesity, hypertension, and diabetes are among the high-risk category groups more prone to SARS-CoV-2 infection. Magnesium has been reported to play a major role both in physiology and in pathology, particularly in elderly people, regulating cytotoxic functions of natural killer (NK) cells and CD8+ T lymphocytes. In spite of the absence of controlled trials, the possibility of magnesium supplementation for supportive treatment in patients with COVID-19 should be encouraged. This could be useful in all phases of the COVID-19 disease.

Copper ions impair zebrafish skeletal myofibrillogenesis via epigenetic regulation

Unbalanced copper (Cu²⁺ ) homeostasis is associated with the developmental defects of vertebrate myogenesis, but the underlying molecular mechanisms remain elusive. In this study, it was found that Cu²⁺ stressed zebrafish embryos and larvae showed reduced locomotor speed as well as loose and decreased myofibrils in skeletal muscle, coupled with the downregulated expression of muscle fiber markers mylpfa and smyhc1l and the irregular arrangement of myofibril and sarcomere. Meanwhile, the Cu²⁺ stressed zebrafish embryos and larvae also showed significant reduction in the expression of H3K4 methyltransferase smyd1b transcripts and H3K4me3 protein as well as in the binding enrichment of H3K4me3 on gene mylpfa promoter in skeletal muscle cells, suggesting that smyd1b-H3K4me3 axis mediates the Cu²⁺ -induced myofibrils specification defects. Additionally, whole genome DNA methylation sequencing unveiled that the gene smyd5 exhibited significant promoter hyper-methylation and increased expression in Cu²⁺ stressed embryos, and the ectopic expression of smyd5 in zebrafish embryos also induced the myofibrils specification defects as those observed in Cu²⁺ stressed embryos. Moreover, Cu²⁺ was shown to suppress myofibrils specification and smyd1b promoter transcriptional activity directly independent of the integral function of copper transporter cox17 and atp7b. All these data may shed light on the linkage of unbalanced copper homeostasis with specific gene promoter methylation and epigenetic histone protein modification as well as the resultant signaling transduction and the myofibrillogenesis defects.

Copper-Induced Epigenetic Changes Shape the Clinical Phenotype in Wilson's Disease

Wilson's disease is a congenital disorder of copper metabolism whose pathogenesis remains, at least in part, unknown. Subjects carrying the same genotype may show completely different phenotypes, differing for the age at illness onset or for the hepatic, neurologic or psychiatric clinical presentation. The inability to find a unequivocal correlation between the type of mutation in the ATPase copper transporting beta (ATP7B) gene and the phenotypic manifestation, has encouraged many authors to look for epigenetic factors interacting with the genetic changes. Here, the evidences regarding the ability of copper overload to change the global DNA methylation status are discussed.

Detecting cadmium during ultrastructural characterization of hepatotoxicity

BACKGROUND

The threat of cadmium (Cd), which is the cause of itai-itai disease in Japan, is still complicated and confusing, especially for digestive system, such as liver disease. One of the most keys of this problem is demonstrating that the hepatotoxicity is indeed induced by Cd. Therefore, we attempt detecting Cd at microscale during ultrastructural imaging of liver tissue.

METHODS

12 rats were divided randomly into two experimental groups: control and Cd-treated. Treated rats were intraperitoneal injected with 1 mg/kg body weight cadmium chloride (CdCl₂) for 4 weeks (5 P.M each day for 6 days/week). At the end of the exposure period, liver tissue samples were processed into ultrathin sections for analysis of advanced analytical transmission electron microscopy and X-ray energy dispersive spectroscopy (TEM/X-EDS) investigations. Ultrastructural images and X-ray energy dispersive spectrum were acquired at microscale.

RESULTS

Cd can cause changes in the structure of the organelle, including the collapse of the membrane structure in the cell, the destruction of the internal structure of the organelle, the mitochondrial swelling, the expansion of the endoplasmic reticulum, and the appearance of inclusions. Cadmium bioaccumulation is detected in the mitochondria at microscale by TEM/X-EDS, which is the visual evidence of morphological changes of mitochondria related to Cd.

CONCLUSION

The combination of detailed ultrastructure and microscale X-ray energy dispersive spectroscopy (X-EDS) characterization of cadmium hepatotoxicity demonstrate that cadmium indeed leads to mitochondrial damage, which is helpful for further investigation of the pathological mechanism of cadmium hepatotoxicity.

Accurate Measurement of Copper Overload in an Experimental Model of Wilson Disease by Laser Ablation Inductively Coupled Plasma Mass Spectrometry

Wilson disease is a rare inherited autosomal recessive disorder. As a consequence of genetic alterations in the ATP7B gene, copper begins to accumulate in the body, particularly in the liver and brain. Affected persons are prone to develop liver cancer and severe psychiatric and neurological symptoms. Clinically, the development of corneal Kayser-Fleischer rings and low ceruloplasmin concentrations (<20 mg/dL) are indicative of Wilson disease. However, the detection of elevated hepatic copper content (>250 µg/g dry weight) alone is still considered as the best but not exclusive diagnostic test for Wilson disease. Presently, specific copper stains (e.g., rhodanine) or indirect staining for copper-associated proteins (e.g., orcein) are widely used to histochemically visualize hepatic copper deposits. However, these procedures only detect lysosomal copper, while cytosolic copper is not detectable. Similarly, elemental analysis in scanning electron microscope with energy dispersive X-ray analysis (EDX) often leads to false negative results and inconsistencies. Here, we tested the diagnostic potential of laser ablation inductively-coupled mass spectrometry (LA-ICP-MS) that allows quantitative analysis of multiple elements. Comparative studies were performed in wild type and the Atp7b null mouse model. We propose LA-ICP-MS as a versatile and powerful method for the accurate determination of hepatic copper in people with Wilson disease with high spatial resolution.

Structural alteration within fly ash-based geopolymers governing the adsorption of Cu2+ from aqueous environment: Effect of alkali activation

Fly-ash based geopolymers have been considered as a low-cost yet effective adsorbent for the removal of heavy metal cations, including Cu²⁺, from the aqueous environment. In the synthesis of geopolymers, the fly-ash needs to be alkali activated using several systems rich in either Na⁺ or K⁺. Herein, we investigate the effect of alkali activation on the structural alteration and its consequence on the adsorption capacity. Based on the series of detailed characterizations, the geopolymers formed in Na⁺-based alkali system is found to have more organized structure compared to that formed in K⁺-based alkali system. Moreover, the incorporation of additional silicate creates ancillary structure which positively contributes to the organization of the overall structure. All the samples, fly-ash and geopolymers, exhibits Cu²⁺ adsorption based on Langmuir isotherm and pseudo-second order kinetic. The geopolymers with more organized structure display higher Cu²⁺ adsorption capacity, which reaches 40 mg g^-1 higher in comparison to 7 mg g^-1 for fly ash sample. The structural alteration induces the formation of open-framework structure with more accessible sites which can accommodate more Cu²⁺. Our study provides a fundamental understanding for the design and fabrication of geopolymers as an effective adsorbent for the removal of heavy metal cations.

Liver pathology in Wilson's disease: From copper overload to cirrhosis

Wilson's disease (WD) is a genetic metabolic disease strictly associated with liver cirrhosis. In this review, the genetic bases of the disease are discussed, with emphasis on the role of ATP7B (the Wilson disease protein) dysfunction as a determinant factor of systemic copper overload. Regarding the different multiple mutations described in WD patients, the peculiarity of Sardinian population is highlighted, Sardinians carrying a rare deletion in the promoter (5' UTR) of the WD gene. The role of epigenetic changes in the clinical presentation and evolution of liver disease in WD patients is also discussed, nutrition probably representing a relevantly risk factor in WD patients. The role of transmission electron microscopy in the diagnosis of WD-related liver disease is underlined. Mitochondrial changes, increased peroxisomes fat droplets, lipolysosomes and intranuclear glycogen inclusions are reported as the most frequent ultrastructural changes in the liver of WD carriers. The role of histochemical stains for copper is analyzed, and the Timm's method is suggested as the most sensitive one for revealing hepatic copper overload in all stage of WD. The marked variability of the histological liver changes occurring in WD is underlined simple steatosis may represent the only pathological changes, frequently associated with glycogenated nuclei. Mallory-Denk bodies lipogranulomas alcoholic and non-alcoholic fatty liver disease ending with bridging fibrosis and cirrhosis. Finally, the reversal of fibrosis as a possible therapeutic objective in WD is discussed.

Evaluation of gold nanorods toxicity on isolated mitochondria

Gold nanorods (AuNRs) have been studied extensively in biomedicine due to their biocompatibility and their unique properties. Some studies reported that AuNRs selectively accumulate on cancer cell mitochondria causing its death. However, the immediate effects of this accumulation needed further investigations. In this context, we evaluated the effect of AuNRs on the mitochondrial integrity of isolated rat liver mitochondria. We verified that AuNRs decreased the mitochondrial respiratory ratio by decreasing the phosphorylation and maximal states. Additionally, AuNRs caused a decrease in the production of mitochondrial ROS and a delay in mitochondrial swelling. Moreover, even with cyclosporine A treatment, AuNRs disrupted the mitochondrial potential. With the highest concentration of AuNRs studied, disorganized mitochondrial crests and intermembrane separation were observed in TEM images. These results indicate that AuNRs can interact with mitochondria, disrupting the electron transport chain. This study provides new evidence of the immediate effects of AuNRs on mitochondrial bioenergetics.

Structural basis for promotion of duodenal iron absorption by enteric ferric reductase with ascorbate

Dietary iron absorption is regulated by duodenal cytochrome b (Dcytb), an integral membrane protein that catalyzes reduction of nonheme Fe³⁺ by electron transfer from ascorbate across the membrane. This step is essential to enable iron uptake by the divalent metal transporter. Here we report the crystallographic structures of human Dcytb and its complex with ascorbate and Zn²⁺. Each monomer of the homodimeric protein possesses cytoplasmic and apical heme groups, as well as cytoplasmic and apical ascorbate-binding sites located adjacent to each heme. Zn²⁺ coordinates to two hydroxyl groups of the apical ascorbate and to a histidine residue. Biochemical analysis indicates that Fe³⁺ competes with Zn²⁺ for this binding site. These results provide a structural basis for the mechanism by which Fe³⁺ uptake is promoted by reducing agents and should facilitate structure-based development of improved agents for absorption of orally administered iron.

Highly efficient and energy-conserved flocculation of copper in wastewater by pulse-alternating current

Copper wastewater from industry is detrimental to plants and environment. There are some problems in the aspects of high efficiency and energy saving during treatment of wastewater. In present work, the novel double iron electrodes technique of pulse-alternating current was applied to flocculate copper in wastewater. The process parameters of the copper removal in wastewater were studied in the developed electrochemical reactors. Scanning electron microscopy, X-ray diffraction, and energy-dispersive spectroscopy were used to characterize the electrocoagulations. The copper residue in the effluent was measured by UV spectrophotometry. The adsorption mechanism was described through the isothermal adsorption curves of copper during flocculation processes. The simulated wastewater containing 100 mg dm^-3 Cu²⁺ and 100 mg dm^-3 NaCl as conductive salt was adjusted to pH 7.8-8 with ammonia or sulfuric acid. At room temperature of 20-25 °C, controlling the flow rate of 3 dm³ min^-1, and applying pulse-alternating current of 40 μA g_Fe^-1, the copper residue in the effluent passing through four-series reactors was reduced to 0.118 mg dm^-3, which was far lower than 0.3 mg dm^-3 (from GB20900-2008). The removal rate of copper could reach 99.882%. The removal of copper in the wastewater treated via our electrocoagulation technique was far more efficient than the conventional DC current coagulation and chemical flocculation. The double iron electrodes were used to reduce the concentration polarization and improved the current efficiency. The significant economic and good social benefit will be promisingly produced if our developed technique is applied in the treatment of industrial wastewater.

Liver stiffness assessed by transient elastography in patients with β thalassaemia major

RATIONALE FOR THE STUDY

This cross-sectional multicenter study was conducted to investigate any difference in liver stiffness measurements (LSM), evaluated by transient elastography, between patients affected by β thalassaemia major, with and without hepatitis C virus (HCV) infection, and healthy blood donors (controls). Secondary aim was to assess any correlation between transient elastography and serum ferritin, liver magnetic resonance imaging (MRI) T2* or superconductive quantum interference device (SQUID) liver susceptometry values.

MATERIALS AND METHODS

The study involved three centers. Transient elastography and MRI T2* examinations were performed in all centers. SQUID liver susceptometry was performed in center1 and center2. T-test for independent data or Mann-Whitney U test was used to analyse differences between two groups. Univariate Pearson's r coefficient was used to test correlations between liver stiffness measurements and all other variables.

RESULTS

In a study with 119 patients and 183 controls, patients who had never been infected with HCV showed significantly higher LSMs than controls [5.7 (95% CI, 5.2-6.2) kPa vs. 4.3 (95% CI, 4.1-4.4) kPa, p < 0.0001]. A moderate correlation between LSMs and ferritin values, adjusted for gender and age, was found in patients (r = 0.49, p < 0.0001) but not in controls (r = -0.22, p = 0.6). No correlation between LSMs and MRI T2* or SQUID liver susceptometry values was observed. In conclusion, compared to controls β thalassaemia major patients had a significant increase in LSMs independently from HCV infection.

Neurotoxicity of Copper

Copper is an essential trace metal that is required for several important biological processes, however, an excess of copper can be toxic to cells. Therefore, systemic and cellular copper homeostasis is tightly regulated, but dysregulation of copper homeostasis may occur in disease states, resulting either in copper deficiency or copper overload and toxicity. This chapter will give an overview on the biological roles of copper and of the mechanisms involved in copper uptake, storage, and distribution. In addition, we will describe potential mechanisms of the cellular toxicity of copper and copper oxide nanoparticles. Finally, we will summarize the current knowledge on the connection of copper toxicity with neurodegenerative diseases.

Trace metal imaging in diagnostic of hepatic metal disease

The liver is the most central organ and the largest gland of the body that influences and controls a variety of metabolic and catabolic processes. It produces inconceivable many essential proteins, is responsible for the recovery of various food components, degrades toxins, mediates the bile production, and is involved in the excretion of unwanted metabolites. Several of these anabolic or catabolic functions of the liver depend on trace elements. These are either integral part of enzymes, cofactors, or act as chemical catalysts. Therefore, a lack of trace elements can lead to organ failure or systemic illness. Conversely, excessive hepatic trace element deposition resulting from genetic disorders, intoxication, extensive dietary supply, or long-term parenteral nutrition may cause hepatic inflammation, fibrosis, cirrhosis, and even hepatocellular carcinoma. Although specific serum parameters currently allow rough assessment of metal deficit and excess, the precise quantification of hepatic metal content in liver is presently only possible by different titration or staining techniques of biopsy specimens. Recently, novel innovative metal imaging techniques were developed that are on the way to replace these traditional methods. In the present review, we summarize the function of different trace elements in liver health and disease and discuss the present knowledge on how quantitative biometal imaging techniques such as synchrotron X-ray fluorescence microscopy, secondary ion mass spectrometry, and laser ablation inductively coupled plasma mass spectrometry enrich diagnostics in the detection and quantification of hepatic metal disorders. We will further discuss sample preparation, sensitivity, spatial resolution, specificity, quantification strategies, and potential future applications of metal bioimaging in experimental research and clinical daily routine. © 2015 Wiley Periodicals, Inc. Mass Spec Rev 35:666-686, 2016.

Chronic hepatitis without hepatic steatosis caused by citrin deficiency in a child

Citrin deficiency manifests as both neonatal intrahepatic cholestasis (NICCD) during early infancy and adult-onset type II citrullinemia during adulthood. Hepatic steatosis is most frequently observed in patients with citrin deficiency. Thus, non-alcoholic fatty liver disease that is unrelated to being overweight is considered one of the clinical features of citrin deficiency in children and adults. However, it remains unknown whether citrin deficiency is a cause of chronic hepatitis in the absence of fatty changes to the liver that occur during childhood. We encountered an 8-year-old girl who showed no clinical features of NICCD during infancy and had persistently elevated transaminase levels for several years. Liver biopsy showed widening of the portal tracts with intense mononuclear cell infiltration and mild fibrosis but no fatty changes. However, she had peculiar dietary habits similar to those that have been observed in many patients with citrin deficiency. In addition, a slightly elevated plasma citrulline level and a high pancreatic secretory trypsin inhibitor level were detected by blood examination, and she was diagnosed with citrin deficiency. Analysis of the SLC25A13 gene revealed the presence of the compound heterozygous mutations 851del4 and IVS13 + 1G > A. Thus, citrin deficiency should be included in the differential diagnosis of chronic hepatitis in children, even in the absence of hepatic steatosis.