The Role of Zinc and Zinc Homeostasis in Macrophage Function

The c.503A>G polymorphism in ZIP1-II of Pacific oyster Crassostrea gigas associated with zinc content

The Pacific oyster Crassostrea gigas is renowned for its high zinc content, but the significant variation among individuals diminishes its value as a reliable source of zinc supplementation. The Zrt/Irt-like protein 1 (ZIP1), a pivotal zinc transporter that facilitates zinc uptake in various organisms, plays crucial roles in regulating zinc content. In the present study, polymorphisms of a ZIP1 gene in C. gigas (CgZIP1-II) were investigated, and their association with zinc content was evaluated through preliminary association analysis in 41 oysters and verification analysis in another 200 oysters. A total of 17 single nucleotide polymorphisms (SNPs) were identified in the exonic region of CgZIP1-II gene, with c.503A>G significantly associated with zinc content. Protein sequence and structure prediction showed that c.503A>G caused a p.Met110Val nonsynonymous mutation located in the metal-binding region of CgZIP1-II, which could influence its affinity for zinc ions, thereby modulating its zinc transport functionality. These results indicate the potential influence of CgZIP1-II polymorphisms on zinc content and provide candidate markers for selecting C. gigas with high zinc content.

Iron, copper, zinc and magnesium on rheumatoid arthritis: a two-sample Mendelian randomization study

This study aimed to elucidate the causal genetic relationships between iron, copper, zinc, magnesium, and rheumatoid arthritis (RA). A two-sample Mendelian randomization (MR) analysis was conducted using the "TwoSampleMR" and "MendelianRandomization" packages in R. The random-effects inverse variance-weighted (IVW) method was used as the primary approach. We performed sensitivity analyses to test the reliability of the results. The random-effects IVW analysis revealed that there was no genetic causal relationship between iron (P = 0.429, odds ratio [OR] 95% confidence interval [CI] = 0.919 [0.746-1.133]), copper (P = 0.313, OR 95% CI = 0.973 [0.921-1.027]), zinc (P = 0.633, OR 95% CI = 0.978 [0.891-1.073]), or magnesium (P = 0.218, OR 95% CI = 0.792 [0.546-1.148]) and RA. Sensitivity analysis verified the reliability of the results. Therefore, there is no evidence to support a causal relationship between iron, copper, zinc, and magnesium intake at the genetic level and the development of RA.

Zinc and Inflammatory Bowel Disease: From Clinical Study to Animal Experiment

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract (GI) with a high incidence rate globally, and IBD patients are often accompanied by zinc deficiency. This review aims to summarize the potential therapeutic value of zinc supplementation in IBD clinical patients and animal models. Zinc supplementation can relieve the severity of IBD especially in patients with zinc deficiency. The clinical severity of IBD were mainly evaluated through some scoring methods involving clinical performance, endoscopic observation, blood biochemistry, and pathologic biopsy. Through conducting animal experiments, it has been found that zinc plays an important role in alleviating clinical symptoms and improving pathological lesions. In both clinical observation and animal experiment of IBD, the therapeutic mechanisms of zinc interventions have been found to be related to immunomodulation, intestinal epithelial repair, and gut microbiota's balance. Furthermore, the antioxidant activity of zinc was clarified in animal experiment. Appropriate zinc supplementation is beneficial for IBD therapy, and the present evidence highlights that alleviating zinc-deficient status can effectively improve the severity of clinical symptoms in IBD patients and animal models.

Alterations in trace elements and cation profiles in transfusion-dependent thalassemia patients

BACKGROUND

Transfusion-dependent thalassemia (TDT) is a severe form of beta-thalassemia, characterized by defective-globin production, resulting in a buildup of unpaired alpha globin chains. Patients with TDT can only survive if they receive safe blood transfusions regularly, which causes iron overload in their blood, which causes a variety of disorders. Cations and trace elements in TDT patients as a drug target deserve more studies.

OBJECTIVES

In the present study, the cations and some trace elements were studied in TDT patients as a tool to adjust their level in the case of any disturbances.

METHODS

Serum calcium, magnesium, zinc, copper, and iron were measured spectrophotometrically while manganese and cobalt were measured by flameless atomic absorption spectroscopy in 100 TDT patients and compared with 35 healthy control children.

RESULTS

Patients with TDT exhibit a notable elevation in blood levels of iron, copper, copper/zinc ratio, and manganese, with a substantial reduction in serum levels of zinc, magnesium, calcium, and cobalt, as compared to the control group. These minerals have diverse associations with clinical data and transfusion frequencies. The receiver operating characteristic (ROC) analysis revealed that the elevated levels of iron, manganese, and calcium exhibit the greatest diagnostic capability, with a sensitivity and specificity of over 80 %, and a Youdin's J value of more than 0.6.

CONCLUSION

The levels of cations and trace elements are disturbed in TDT patients. Hence, the monitoring and adjustment of the level of these minerals are important to prevent further consequences.

Tracking the Cellular Degradation of Silver Nanoparticles: Development of a Generic Kinetic Model

Understanding the degradation of nanoparticles (NPs) after crossing the cell plasma membrane is crucial in drug delivery designs and cytotoxicity assessment. However, the key factors controlling the degradable kinetics remain unclear due to the absence of a quantification model. In this study, subcellular imaging of silver nanoparticles (AgNPs) was used to determine the intracellular transfer of AgNPs, and single particle ICP-MS was utilized to track the degradation process. A cellular kinetic model was subsequently developed to describe the uptake, transfer, and degradation behaviors of AgNPs. Our model demonstrated that the intracellular degradation efficiency of AgNPs was much higher than that determined by mimicking testing, and the degradation of NPs was highly influenced by cellular factors. Specifically, deficiencies in Ca or Zn primarily decreased the kinetic dissolution of NPs, while a Ca deficiency also resulted in the retardation of NP transfer. The biological significance of these kinetic parameters was strongly revealed. Our model indicated that the majority of internalized AgNPs dissolved, with the resulting ions being rapidly depurated. The release of Ag ions was largely dependent on the microvesicle-mediated route. By changing the coating and size of AgNPs, the model results suggested that size influenced the transfer of NPs into the degradation process, whereas coating affected the degradation kinetics. Overall, our developed model provides a valuable tool for understanding and predicting the impacts of the physicochemical properties of NPs and the ambient environment on nanotoxicity and therapeutic efficacy.

Meta-analysis of the Relationship Between Zinc and Copper in Patients with Osteoarthritis

This study aims to explore the relationship between osteoarthritis and the trace elements zinc and copper and to provide a theoretical basis for research on the related mechanisms for the prevention, diagnosis, and treatment of osteoarthritis. We searched all the literature indexed in Web Of Science, Embase, and PubMed as of January 10, 2024, summarized the zinc and copper detection indexes in patients with osteoarthritis, obtained clinical data through literature screening, quality assessment, and data extraction, and analyzed the data using Revman 5.4. A total of 13 papers were included in this study, totaling 7983 study subjects. These were divided into osteoarthritis and healthy control groups. The results from the meta-analysis showed that in patients with osteoarthritis, circulating copper levels, but not zinc levels, were significantly higher compared to healthy individuals. The level of copper in the blood of patients with osteoarthritis is significantly higher than that of healthy people.

The nutritional roles of zinc for immune system and COVID-19 patients

Zinc (Zn) is a vital micronutrient that strengthens the immune system, aids cellular activities, and treats infectious diseases. A deficiency in Zn can lead to an imbalance in the immune system. This imbalance is particularly evident in severe deficiency cases, where there is a high susceptibility to various viral infections, including COVID-19 caused by SARS-CoV-2. This review article examines the nutritional roles of Zn in human health, the maintenance of Zn concentration, and Zn uptake. As Zn is an essential trace element that plays a critical role in the immune system and is necessary for immune cell function and cell signaling, the roles of Zn in the human immune system, immune cells, interleukins, and its role in SARS-CoV-2 infection are further discussed. In summary, this review paper encapsulates the nutritional role of Zn in the human immune system, with the hope of providing specific insights into Zn research.

Multiscale architecture design of 3D printed biodegradable Zn-based porous scaffolds for immunomodulatory osteogenesis

Reconciling the dilemma between rapid degradation and overdose toxicity is challenging in biodegradable materials when shifting from bulk to porous materials. Here, we achieve significant bone ingrowth into Zn-based porous scaffolds with 90% porosity via osteoinmunomodulation. At microscale, an alloy incorporating 0.8 wt% Li is employed to create a eutectoid lamellar structure featuring the LiZn4 and Zn phases. This microstructure optimally balances high strength with immunomodulation effects. At mesoscale, surface pattern with nanoscale roughness facilitates filopodia formation and macrophage spreading. At macroscale, the isotropic minimal surface G unit exhibits a proper degradation rate with more uniform feature compared to the anisotropic BCC unit. In vivo, the G scaffold demonstrates a heightened efficiency in promoting macrophage polarization toward an anti-inflammatory phenotype, subsequently leading to significantly elevated osteogenic markers, increased collagen deposition, and enhanced new bone formation. In vitro, transcriptomic analysis reveals the activation of JAK/STAT pathways in macrophages via up regulating the expression of Il-4, Il-10, subsequently promoting osteogenesis.

Morphology, Development, and Pigment Production of Talaromyces marneffei are Diversely Modulated Under Physiologically Relevant Growth Conditions

Talaromyces marneffei is an opportunistic pathogenic fungus that mainly affects HIV-positive individuals endemic to Southeast Asia and China. Increasing efforts have been made in the pathogenic mechanism and host interactions understanding of this pathogen in the last two decades; however, there are still no conclusions on how T. marneffei was transmitted from the donor bamboo rats to humans. A perception that the failure of fungus isolation from soil was attributed to the low salt tolerance of T. marneffei. Therefore, the effect of environmental fluctuations in fungal growth and development is fundamental for the characterization of its origin and fungal biology understanding. Herein, we characterized high osmolarity, pH, metal ions, nutrients, and oxidative stress have versatile effects on T. marneffei hyphal or yeast growth, conidia generation, and pigment production. Among these, high pH, low glucose amounts, and the inorganic nitrogen ammonium tartrate stimulated the red pigment production, whereas high osmolarity, high pH, and the inorganic nitrogen sodium nitrate could significantly accelerate the conidia generation. Specifically, zinc starvation repressed conidia generation and prevented the wrinkled yeast colony formation, indicating the function of zinc regulators in pathogenicity regulation. Since conidia are recognized as the infectious propagules, the effects characterization of different environmental factors in T. marneffei morphology in this work will not only expand the growth and pathogenic biology understanding of the fungus but also provide more clues for the T. marneffei infection transmission origin investigation.

Preventing and Controlling Zinc Deficiency Across the Life Course: A Call to Action

Through diverse roles, zinc determines a greater number of critical life functions than any other single micronutrient. Beyond the well-recognized importance of zinc for child growth and resistance to infections, zinc has numerous specific roles covering the regulation of glucose metabolism, and growing evidence links zinc deficiency with increased risk of diabetes and cardiometabolic disorders. Zinc nutriture is, thus, vitally important to health across the life course. Zinc deficiency is also one of the most common forms of micronutrient malnutrition globally. A clearer estimate of the burden of health disparity attributable to zinc deficiency in adulthood and later life emerges when accounting for its contribution to global elevated fasting blood glucose and related noncommunicable diseases (NCDs). Yet progress attenuating its prevalence has been limited due, in part, to the lack of sensitive and specific methods to assess human zinc status. This narrative review covers recent developments in our understanding of zinc's role in health, the impact of the changing climate and global context on zinc intake, novel functional biomarkers showing promise for monitoring population-level interventions, and solutions for improving population zinc intake. It aims to spur on implementation of evidence-based interventions for preventing and controlling zinc deficiency across the life course. Increasing zinc intake and combating global zinc deficiency requires context-specific strategies and a combination of complementary, evidence-based interventions, including supplementation, food fortification, and food and agricultural solutions such as biofortification, alongside efforts to improve zinc bioavailability. Enhancing dietary zinc content and bioavailability through zinc biofortification is an inclusive nutrition solution that can benefit the most vulnerable individuals and populations affected by inadequate diets to the greatest extent.

CFTR is required for zinc-mediated antibacterial defense in human macrophages

Cystic fibrosis transmembrane conductance regulator (CFTR) is an anion transporter required for epithelial homeostasis in the lung and other organs, with CFTR mutations leading to the autosomal recessive genetic disease CF. Apart from excessive mucus accumulation and dysregulated inflammation in the airways, people with CF (pwCF) exhibit defective innate immune responses and are susceptible to bacterial respiratory pathogens such as Pseudomonas aeruginosa. Here, we investigated the role of CFTR in macrophage antimicrobial responses, including the zinc toxicity response that is used by these innate immune cells against intracellular bacteria. Using both pharmacological approaches, as well as cells derived from pwCF, we show that CFTR is required for uptake and clearance of pathogenic Escherichia coli by CSF-1-derived primary human macrophages. CFTR was also required for E. coli-induced zinc accumulation and zinc vesicle formation in these cells, and E. coli residing in macrophages exhibited reduced zinc stress in the absence of CFTR function. Accordingly, CFTR was essential for reducing the intramacrophage survival of a zinc-sensitive E. coli mutant compared to wild-type E. coli. Ectopic expression of the zinc transporter SLC30A1 or treatment with exogenous zinc was sufficient to restore antimicrobial responses against E. coli in human macrophages. Zinc supplementation also restored bacterial killing in GM-CSF-derived primary human macrophages responding to P. aeruginosa, used as an in vitro macrophage model relevant to CF. Thus, restoration of the zinc toxicity response could be pursued as a therapeutic strategy to restore innate immune function and effective host defense in pwCF.

Integrating osteoimmunology and nanoparticle-based drug delivery systems for enhanced fracture healing

Fracture healing is a complex interplay of molecular and cellular mechanisms lasting from days to weeks. The inflammatory phase is the first stage of fracture healing and is critical in setting the stage for successful healing. There has been growing interest in exploring the role of the immune system and novel therapeutic strategies, such as nanoparticle drug delivery systems in enhancing fracture healing. Advancements in nanotechnology have revolutionized drug delivery systems to the extent that they can modulate immune response during fracture healing by leveraging unique physiochemical properties. Therefore, understanding the intricate interactions between nanoparticle-based drug delivery systems and the immune response, specifically macrophages, is essential for therapeutic efficacy. This review provides a comprehensive overview of the relationship between the immune system and nanoparticles during fracture healing. Specifically, we highlight the influence of nanoparticle characteristics, such as size, surface properties, and composition, on macrophage activation, polarization, and subsequent immune responses. IMPACT STATEMENT: This review provides valuable insights into the interplay between fracture healing, the immune system, and nanoparticle-based drug delivery systems. Understanding nanoparticle-macrophage interactions can advance the development of innovative therapeutic approaches to enhance fracture healing, improve patient outcomes, and pave the way for advancements in regenerative medicine.

The Role of Zinc in Bone Tissue Health and Regeneration-a Review

Zinc is a micronutrient of key importance for human health. An increasing number of studies indicate that zinc plays a significant role in bone tissue's normal development and maintaining homeostasis. Zinc is not only a component of bone tissue but is also involved in the synthesis of the collagen matrix, mineralization, and bone turnover. It has been demonstrated that zinc can stimulate runt-related transcription factor 2 (Runx2) and promote the differentiation of osteoblasts. On the other hand, zinc has been found to inhibit osteoclast-like cell formation and to decrease bone resorption by stimulating osteoclasts' apoptosis. Moreover, zinc regulates the RANKL/RANK/OPG pathway, thereby facilitating bone remodeling. To date, not all mechanisms of Zn activity on bone tissue are well understood and documented. The review aimed to present the current state of research on the role of zinc in bone tissue, its beneficial properties, and its effects on bone regeneration. Since calcium phosphates as bone substitute materials are increasingly enriched in zinc ions, the paper included an overview of research on the potential role of such materials in bone filling and regeneration.

Zinc deficiency impairs axonal regeneration and functional recovery after spinal cord injury by modulating macrophage polarization via NF-κB pathway

Background

Spinal cord injury (SCI) is a devastating disease that results in permanent paralysis. Currently, there is no effective treatment for SCI, and it is important to identify factors that can provide therapeutic intervention during the course of the disease. Zinc, an essential trace element, has attracted attention as a regulator of inflammatory responses. In this study, we investigated the effect of zinc status on the SCI pathology and whether or not zinc could be a potential therapeutic target.

Methods

We created experimental mouse models with three different serum zinc concentration by changing the zinc content of the diet. After inducing contusion injury to the spinal cord of three mouse models, we assessed inflammation, apoptosis, demyelination, axonal regeneration, and the number of nuclear translocations of NF-κB in macrophages by using qPCR and immunostaining. In addition, macrophages in the injured spinal cord of these mouse models were isolated by flow cytometry, and their intracellular zinc concentration level and gene expression were examined. Functional recovery was assessed using the open field motor score, a foot print analysis, and a grid walk test. Statistical analysis was performed using Wilcoxon rank-sum test and ANOVA with the Tukey-Kramer test.

Results

In macrophages after SCI, zinc deficiency promoted nuclear translocation of NF-κB, polarization to pro-inflammatory like phenotype and expression of pro-inflammatory cytokines. The inflammatory response exacerbated by zinc deficiency led to worsening motor function by inducing more apoptosis of oligodendrocytes and demyelination and inhibiting axonal regeneration in the lesion site compared to the normal zinc condition. Furthermore, zinc supplementation after SCI attenuated these zinc-deficiency-induced series of responses and improved motor function.

Conclusion

We demonstrated that zinc affected axonal regeneration and motor functional recovery after SCI by negatively regulating NF-κB activity and the subsequent inflammatory response in macrophages. Our findings suggest that zinc supplementation after SCI may be a novel therapeutic strategy for SCI.

The changes and potential effects of zinc homeostasis in periodontitis microenvironment

Zinc is a very important and ubiquitous element, which is present in oral environment, daily diet, oral health products, dental restorative materials, and so on. However, there is a lack of attention to the role of both extracellular or intracellular zinc in the progression of periodontitis and periodontal regeneration. This review summarizes the characteristics of immunological microenvironment and host cells function in several key stages of periodontitis progression, and explores the regulatory effect of zinc during this process. We find multiple evidence indicate that zinc may be involved and play a key role in the stages of immune defense, inflammatory response and bone remodeling. Zinc supplementation in an appropriate dose range or regulation of zinc transport proteins can promote periodontal regeneration by either enhancing immune defense or up-regulating local cells proliferation and differentiation functions. Therefore, zinc homeostasis is essential in periodontal remodeling and regeneration. More attention is suggested to be focused on zinc homeostasis regulation and consider it as a potential strategy in the studies on periodontitis treatment, periodontal-guided tissue regeneration, implant material transformation, and so on.

ZNT1 and Zn 2+ control TLR4 and PD-L1 endocytosis in macrophages to improve chemotherapy efficacy against liver tumor

BACKGROUND AND AIMS

HCC is closely associated with inflammation and immune modulation, and combined chemotherapy with other strategies is under extensive investigation to achieve better efficacy. HCC is accompanied by zinc (Zn) deficiency. This study aims to understand how Zn could affect macrophage function and its application for HCC therapy.

APPROACH AND RESULTS

Zn 2+ and the Zn transporter 1 (ZNT1, solute carrier family 30 member 1) were markedly reduced in intrahepatic macrophages from patients with HCC and from mouse liver tumors. Lower ZNT1 expression was associated with higher IL-6 production and shorter survival time in patients with HCC. Critically, ZNT1 regulated endosomal Zn 2+ levels for endocytosis of toll-like receptor 4 and programmed cell death ligand 1, thereby decreasing macrophage-induced inflammation and immunosuppression to protect from liver tumors. Myeloid-specific deletion of ZNT1 in mice increased chronic inflammation, liver fibrosis, tumor numbers, and size. Notably, Zn supplementation could reduce inflammation and surface programmed cell death ligand 1 expression in macrophages with the increased CD8 + T cell cytotoxicity, which synergized the antitumor efficacy of Sorafenib/Lenvatinib.

CONCLUSIONS

Our study proposes a new concept that ZNT1 and Zn regulate endosome endocytosis to maintain surface receptors, and Zn supplements might be synergized with chemotherapy to treat inflammation-associated tumors, especially those containing programmed cell death ligand 1 + myeloid cells.

Therapeutic effect of trace elements on multiple myeloma and mechanisms of cancer process

In the human body, trace elements and other micronutrients play a vital role in growth, health and immune system function. The trace elements are Iron, Manganese, Copper, Iodine, Zinc, Cobalt, Fluoride, and Selenium. Estimating the serum levels of trace elements in hematologic malignancy patients can determine the severity of the tumor. Multiple myeloma (MM) is a hematopoietic malignancy and is characterized by plasma cell clonal expansion in bone marrow. Despite the advances in treatment methods, myeloma remains largely incurable. In addition to conventional medicine, treatment is moving toward less expensive noninvasive alternatives. One of the alternative treatments is the use of dietary supplements. In this review, we focused on the effect of three trace elements including iron, zinc and selenium on important mechanisms such as the immune system, oxidative and antioxidant factors and cell cycle. Using some trace minerals in combination with approved drugs can increase patients' recovery speed. Trace elements can be used as not only a preventive but also a therapeutic tool, especially in reducing inflammation in hematological cancers such as multiple myeloma. We hope that the prospect of the correct use of trace element supplements in the future could be promising for the treatment of diseases.

Evolution from Bioinert to Bioresorbable: In Vivo Comparative Study of Additively Manufactured Metal Bone Scaffolds

Additively manufactured scaffolds offer significant potential for treating bone defects, owing to their porous, customizable architecture and functionalization capabilities. Although various biomaterials have been investigated, metals - the most successful orthopedic material - have yet to yield satisfactory results. Conventional bio-inert metals, such as titanium (Ti) and its alloys, are widely used for fixation devices and reconstructive implants, but their non-bioresorbable nature and the mechanical property mismatch with human bones limit their application as porous scaffolds for bone regeneration. Advancements in additive manufacturing have facilitated the use of bioresorbable metals, including magnesium (Mg), zinc (Zn), and their alloys, as porous scaffolds via Laser Powder Bed Fusion (L-PBF) technology. This in vivo study presents a comprehensive, side-by-side comparative analysis of the interactions between bone regeneration and additively manufactured bio-inert/bioresorbable metal scaffolds, as well as their therapeutic outcomes. The research offers an in-depth understanding of the metal scaffold-assisted bone healing process, illustrating that Mg and Zn scaffolds contribute to the bone healing process in distinct ways, but ultimately deliver superior therapeutic outcomes compared to Ti scaffolds. These findings suggest that bioresorbable metal scaffolds hold considerable promise for the clinical treatment of bone defects in the near future.

Effect of combined in ovo administration of zinc glycine chelate (Zn-Gly) and a multistrain probiotic on the modulation of cellular and humoral immune responses in broiler chickens

The aim of the study was to determine the effect of in ovo administration of zinc glycine chelate (Zn-Gly), and a multistrain probiotic on the hatchability and selected parameters of the cellular and humoral immune response of chickens. The study was conducted on 1,400 fertilized eggs from commercial broiler breeders (Ross x Ross 708). Material for the study consisted of peripheral blood and spleens of chicks taken 12 h and 7 d after hatching. The results showed that both combined and single in ovo administration of the multistrain probiotic and zinc glycine chelate significantly reduced hatchability of chicks. The flow cytometry study showed that the highest percentage of CD4+ T cells, CD4+CD25+, and high expression of KUL01 in the serum were obtained in the group supplemented with probiotic and Zn-Gly both 12 h and 7 d after hatching. In birds supplemented with probiotic and zinc chelate, a high percentage of TCRγδ+ cells was found in serum and spleen 12 h after hatching and in serum after 7 d. The percentage of Bu-1A+ lymphocytes in serum and spleen 12 h and 7 d after hatching was the highest in the group supplemented with probiotic and Zn-Gly. The highest expression of CD79A was observed in the group supplemented only with zinc chelate. There were no significant differences in the percentage of CD4+ cells in the spleens of birds in the groups receiving the multistrain probiotic at 12 h after hatching, and after 7 d, the percentage of CD4+ T cells was lower in the experimental groups than in the control group. The percentage of CD8+ cells in the serum of birds after hatching was lower in the group supplemented with multistrain probiotic and Zn-Gly than in the control group, but reached the highest value on d 7 after hatching. The obtained results confirm the strong effect of the combined administration of a multistrain probiotic and Zn-Gly chelate on lymphocyte proliferation and stimulation of cellular immune mechanisms in birds.

Trends and hotspots of publications on ferroptosis: A 10 Year overview

Background

Ferroptosis was proposed to be a type of programmed cell death in 2012. Ferroptosis plays a significant role in a variety of illnesses.

Objective

To better understand the direction of future research, we performed a bibliometric analysis to identify research hotspots with a focus on ferroptosis.

Methods

The search terms [TI = "ferroptosis" OR ("GSH" AND "GPX4") OR "lipid peroxidation" OR "iron homeostasis" OR "iron metabolism"] AND [PY = "2012-2022"] AND [DT = "Article OR Review"] AND [LA = "English"] were used to retrieve publications related to ferroptosis for a bibliometric analysis. We utilized Microsoft Excel to calculate the frequency and proportion of the published articles, VOSviewer to perform a co-occurrence analysis and for visualizing the data, CiteSpace to obtain a timeline of keywords and institutions, and RStudio to calculate citation metrics. As indicated by the analysis, indicators such as the number of publications, the most productive authors and coauthorship status, the distribution of publications by country, favoured journals, the most influential institutions and the most frequently cited documents are reported in this article.

Results

A total of 8009 publications were retrieved from the WOS core collection, and 197 papers published in 2023 were removed from this analysis. The remaining 7812 papers, which included 118 in the WOS collection, were incorporated into the bibliometric study.

Conclusion

The number of annual scientific publications on ferroptosis have been increasing each year. The academic communities represented by Tang, Daolin, Stockwell, Brent R., Wang, Fudi, and Conrad, Marcus were the most authoritative. China, USA, and Germany were the front-runners in the field of ferroptosis. Free Radical Biology and Medicine was the largest contributor of ferroptosis-related research, and Cell and Nature were the most influential journals to publish articles on ferroptosis. Columbia Univ and Univ Pittsburgh were the institutions that received the most attention. Recent research on ferroptosis has been focused on molecular mechanisms, particularly those in the contexts of various diseases, which will be a hotspot of future research. In addition, interdisciplinary ferroptosis and big-data research is expected to be a new frontier.

Transcriptomic Effects of Low-Dose Inorganic Arsenic Exposure on Murine Bone Marrow-Derived Macrophages

Both tissue-resident macrophages and monocytes recruited from the bone marrow that transform into tissue-resident cells play critical roles in mediating homeostasis as well as in the pathology of inflammatory diseases. Inorganic arsenic (iAs) is the most common drinking water contaminant worldwide and represents a major public health concern. Several diseases that macrophages have implicated involvement in are caused by iAs exposure, including cardiovascular disease, cancer, and increased risk of infectious disease. Therefore, understanding the effects of iAs exposure on macrophages can help us better grasp the full range of arsenic immunotoxicity and better design therapeutic targets for iAs-induced diseases particularly in exposed populations. In this study, we analyzed the transcriptome of low dose iAs-exposed male and female murine bone marrow-derived macrophages (BMDMs) with either M0, M1, or M2 stimulation. We identified differentially expressed genes by iAs in a sex- and stimulation-dependent manner and used bioinformatics tools to predict protein-protein interactions, transcriptional regulatory networks, and associated biological processes. Overall, our data suggest that M1-stimulated, especially female-derived, BMDMs are most susceptible to iAs exposure. Most notably, we observed significant downregulation of major proinflammatory transcription factors, like IRF8, and its downstream targets, as well as genes encoding proteins involved in pattern recognition and antigen presentation, such as TLR7, TLR8, and H2-D1, potentially providing causal insight regarding arsenic's role in perturbing immune responses to infectious diseases. We also observed significant downregulation of genes involved in processes crucial to coordinating a proinflammatory response including leukocyte migration, differentiation, and cytokine and chemokine production and response. Finally, we discovered that 24 X-linked genes were dysregulated in iAs-exposed female stimulation groups compared to only 3 across the iAs-exposed male stimulation groups. These findings elucidate the potential mechanisms underlying the sex-differential iAs-associated immune-related disease risk.

Microglial reprogramming by Hv1 antagonism protects neurons from inflammatory and glutamate toxicity

Although the precise mechanisms determining the neurotoxic or neuroprotective activation phenotypes in microglia remain poorly characterized, metabolic changes in these cells appear critical for these processes. As cellular metabolism can be tightly regulated by changes in intracellular pH, we tested whether pharmacological targeting of the microglial voltage-gated proton channel 1 (Hv1), an important regulator of intracellular pH, is critical for activated microglial reprogramming. Using a mouse microglial cell line and mouse primary microglia cultures, either alone, or co-cultured with rat cerebrocortical neurons, we characterized in detail the microglial activation profile in the absence and presence of Hv1 inhibition. We observed that activated microglia neurotoxicity was mainly attributable to the release of tumor necrosis factor alpha, reactive oxygen species, and zinc. Strikingly, pharmacological inhibition of Hv1 largely abrogated inflammatory neurotoxicity not only by reducing the production of cytotoxic mediators but also by promoting neurotrophic molecule production and restraining excessive phagocytic activity. Importantly, the Hv1-sensitive change from a pro-inflammatory to a neuroprotective phenotype was associated with metabolic reprogramming, particularly via a boost in NADH availability and a reduction in lactate. Most critically, Hv1 antagonism not only reduced inflammatory neurotoxicity but also promoted microglia-dependent neuroprotection against a separate excitotoxic injury. Our results strongly suggest that Hv1 blockers may provide an important therapeutic tool against a wide range of inflammatory neurodegenerative disorders.

Osteoimmunomodulatory Nanoparticles for Bone Regeneration

Treatment of large bone fractures remains a challenge for orthopedists. Bone regeneration is a complex process that includes skeletal cells such as osteoblasts, osteoclasts, and immune cells to regulate bone formation and resorption. Osteoimmunology, studying this complicated process, has recently been used to develop biomaterials for advanced bone regeneration. Ideally, a biomaterial shall enable a timely switch from early stage inflammatory (to recruit osteogenic progenitor cells) to later-stage anti-inflammatory (to promote differentiation and terminal osteogenic mineralization and model the microstructure of bone tissue) in immune cells, especially the M1-to-M2 phenotype switch in macrophage populations, for bone regeneration. Nanoparticle (NP)-based advanced drug delivery systems can enable the controlled release of therapeutic reagents and the delivery of therapeutics into specific cell types, thereby benefiting bone regeneration through osteoimmunomodulation. In this review, we briefly describe the significance of osteoimmunology in bone regeneration, the advancement of NP-based approaches for bone regeneration, and the application of NPs in macrophage-targeting drug delivery for advanced osteoimmunomodulation.

Nutrients in prevention, treatment, and management of viral infections; special focus on Coronavirus

BACKGROUND

The coronavirus disease 2019 (COVID-19) is a pandemic caused by coronavirus with mild to severe respiratory symptoms. This paper aimed to investigate the effect of nutrients on the immune system and their possible roles in the prevention, treatment, and management of COVID-19 in adults.

METHODS

This Systematic review was designed based on the guideline of the Preferred Reporting for Systematic Reviews (PRISMA). The articles that focussed on nutrition, immune system, viral infection, and coronaviruses were collected by searching databases for both published papers and accepted manuscripts from 1990 to 2020. Irrelevant papers and articles without English abstract were excluded from the review process.

RESULTS

Some nutrients are actively involved in the proper functioning and strengthening of the human immune system against viral infections including dietary protein, omega-3 fatty acids, vitamin A, vitamin D, vitamin E, vitamin B₁, vitamin B₆, vitamin B₁₂, vitamin C, iron, zinc, and selenium. Few studies were done on the effect of dietary components on prevention of COVID-19, but supplementation with these nutrients may be effective in improving the health status of patients with viral infections.

CONCLUSION

Following a balanced diet and supplementation with proper nutrients may play a vital role in prevention, treatment, and management of COVID-19. However, further clinical trials are needed to confirm these findings and presenting the strong recommendations against this pandemic.

A Zinc- and Calcium-Rich Lysosomal Nanoreactor Rescues Monocyte/Macrophage Dysfunction under Sepsis

Sepsis is a dysregulation of the immune response to pathogens and has high morbidity and mortality worldwide. However, the unclear mapping and course of dysregulated immune cells currently hinders the development of advanced therapeutic strategies to treat sepsis. Here, evidence is provided using single-cell RNA sequencing from peripheral blood mononuclear cells in sepsis that pathogens attacking monocytes/macrophages disrupt their immune function. The results reveal an enormous decline in monocytes/macrophages in sepsis and chart the evolution of their impaired phagocytosis (Pha) capabilities. Inspired by these findings, nanoparticles, named "Alpha-MOFs," are developed that target dysfunctional monocytes/macrophages to actively (A) lift (L) Pha by the release of lysosome-sensitive ions from a mineralized metal-organic framework (MOF). Alpha-MOFs have good stability and biosafety in peripheral blood and efficiently targeted monocytes/macrophages. They also release calcium and zinc ions into monocyte/macrophage lysosomes to promote the Pha and degradation of bacteria. Taken together, these results suggest that Alpha-MOFs rescue monocytes/macrophages dysfunction and effectively improve their survival rate during sepsis.

SINDy for delay-differential equations: application to model bacterial zinc response

We extend the data-driven method of sparse identification of nonlinear dynamics (SINDy) developed by Brunton et al. , Proc. Natl Acad. Sci. USA 113 (2016) to the case of delay differential equations (DDEs). This is achieved in a bilevel optimization procedure by first applying SINDy for fixed delay and then subsequently optimizing the error of the reconstructed SINDy model over delay times. We test the SINDy-delay method on a noisy short dataset from a toy DDE and show excellent agreement. We then apply the method to experimental data of gene expressions in the bacterium Pseudomonas aeruginosa subject to the influence of zinc. The derived SINDy model suggests that the increase in zinc concentration mainly affects the time delay and not the strengths of the interactions between the different agents controlling the zinc export mechanism.

Circulating Level of Blood Iron and Copper Associated with Inflammation and Disease Activity of Rheumatoid Arthritis

This study aims to compare the concentrations of circulating levels of iron, zinc, and copper in blood samples of rheumatoid arthritis (RA) patients which determine the correlations with inflammation and disease activity. A total of 102 RA patients and 66 healthy controls were enrolled. Circulation of iron, zinc, and copper levels in whole blood were assessed. Hemoglobin, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), anticyclic citrullinated peptide antibody (anti-CCP) levels were collected. A meta-analysis was performed to validate our findings. Single and multiple variate generalized linear regression were applied to identify the correlation between trace elements and clinical characteristics. Blood copper level was significantly higher in RA patients (P < 0.001), while iron and zinc levels were decreased (P < 0.001 and P = 0.02, respectively). Meta-analysis confirmed our findings for zinc (SMD =  - 1.17, P < 0.001) and copper (SMD = 1.24, P < 0.001). Copper level was positively correlated with DAS28-CRP (r = 0.35, P < 0.01), CRP (r = 0.45, P < 0.01) and ESR (r = 0.58, P < 0.01). Iron level was negatively correlated with DAS28-CRP (r =  - 0.37, P < 0.01), CRP (r =  - 0.46, P < 0.01) and ESR (r =  - 0.55, P < 0.01). Circulating blood copper was significantly higher and positively correlated with DAS28-CRP and inflammatory markers, while circulating blood iron was decreased and negatively correlated with DAS28-CRP and inflammatory markers in RA patients.

Agronomic biofortification of food crops: An emerging opportunity for global food and nutritional security

Fortification of food with mineral micronutrients and micronutrient supplementation occupied the center stage during the two-year-long Corona Pandemic, highlighting the urgent need to focus on micronutrition. Focus has also been intensified on the biofortification (natural assimilation) of mineral micronutrients into food crops using various techniques like agronomic, genetic, or transgenic. Agronomic biofortification is a time-tested method and has been found useful in the fortification of several nutrients in several crops, yet the nutrient use and uptake efficiency of crops has been noted to vary due to different growing conditions like soil type, crop management, fertilizer type, etc. Agronomic biofortification can be an important tool in achieving nutritional security and its importance has recently increased because of climate change related issues, and pandemics such as COVID-19. The introduction of high specialty fertilizers like nano-fertilizers, chelated fertilizers, and water-soluble fertilizers that have high nutrient uptake efficiency and better nutrient translocation to the consumable parts of a crop plant has further improved the effectiveness of agronomic biofortification. Several new agronomic biofortification techniques like nutripriming, foliar application, soilless activation, and mechanized application techniques have further increased the relevance of agronomic biofortification. These new technological advances, along with an increased realization of mineral micronutrient nutrition have reinforced the relevance of agronomic biofortification for global food and nutritional security. The review highlights the advances made in the field of agronomic biofortification via the improved new fertilizer forms, and the emerging techniques that achieve better micronutrient use efficiency of crop plants.

The relationship between zinc deficiency and infectious complications in patients with hepatitis B virus-related acute-on-chronic liver failure

BACKGROUND

The prevalence of zinc deficiency is high in patients with chronic liver disease, but few studies have hitherto explored the relationship between the serum zinc level and hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). This study aimed to assess the association between zinc deficiency and infectious complications, and model for end-stage liver disease (MELD) score in patients with HBV-related ACLF.

METHODS

Patients with HBV-related ACLF from the Department of Infectious Diseases of the Third Affiliated Hospital of Sun Yat-sen University (Guangzhou, China) between January 2019 and December 2019 were retrospectively analysed in this study. Their demographic, clinical, and laboratory data were retrieved from the hospital information system and analysed. The Student's t-test was used for normally distributed continuous variables between two groups and the Chi-square test was used for categorical data. Univariate and multivariate logistic regression analyses were applied to identify independent parameters.

RESULTS

A total of 284 patients were included in this study, including 205 liver cirrhosis and 79 non-cirrhosis patients. The proportion of patients with zinc deficiency was the highest (84.5%), followed by subclinical zinc deficiency (14.1%) and normal zinc level (1.4%). Patients in the zinc deficiency group had a higher MELD score than the subclinical zinc deficiency or normal zinc group (P = 0.021). Age, total bilirubin, and serum zinc level were independent factors for infection (Ps < 0.05). The serum zinc level in patients without complications at admission was significantly higher than that in patients with complications (P = 0.004). Moreover, the serum zinc level in patients with prothrombin time activity (PTA) of <20% was significantly lower than that in patients with 20% ≤ PTA < 30% (P = 0.007) and that in patients with 30% ≤ PTA < 40% (P < 0.001).

CONCLUSIONS

Zinc deficiency is common in patients with HBV-related ACLF. Zinc deficiency is closely associated with infectious complications and MELD score in patients with HBV-related ACLF.

Zinc and COVID-19: Immunity, Susceptibility, Severity and Intervention

During the coronavirus disease 2019 (COVID-19) pandemic and continuing emergence of viral mutants, there has been a lack of effective treatment methods. Zinc maintains immune function, with direct and indirect antiviral activities. Zinc nutritional status is a critical factor in antiviral immune responses. Importantly, COVID-19 and zinc deficiency overlap in high-risk population. Hence, the potential effect of zinc as a preventive and adjunct therapy for COVID-19 is intriguing. Here, this review summarizes the immune and antiviral function of zinc, the relationship between zinc levels, susceptibility, and severity of COVID-19, and the effect of zinc supplementation on COVID-19. Existing studies have confirmed that zinc deficiency was associated with COVID-19 susceptibility and severity. Zinc supplementation plays a potentially protective role in enhancing immunity, decreasing susceptibility, shortening illness duration, and reducing the severity of COVID-19. We recommend that zinc levels should be monitored, particularly in COVID-19 patients, and zinc as a preventive and adjunct therapy for COVID-19 should be considered for groups at risk of zinc deficiency to reduce susceptibility and disease severity.

Biodegradable Zn-Cu-Fe Alloy as a Promising Material for Craniomaxillofacial Implants: An in vitro Investigation into Degradation Behavior, Cytotoxicity, and Hemocompatibility

Zinc-based nanoparticles, nanoscale metal frameworks and metals have been considered as biocompatible materials for bone tissue engineering. Among them, zinc-based metals are recognized as promising biodegradable materials thanks to their moderate degradation rate ranging between magnesium and iron. Nonetheless, materials’ biodegradability and the related biological response depend on the specific implant site. The present study evaluated the biodegradability, cytocompatibility, and hemocompatibility of a hot-extruded zinc-copper-iron (Zn-Cu-Fe) alloy as a potential biomaterial for craniomaxillofacial implants. Firstly, the effect of fetal bovine serum (FBS) on in vitro degradation behavior was evaluated. Furthermore, an extract test was used to evaluate the cytotoxicity of the alloy. Also, the hemocompatibility evaluation was carried out by a modified Chandler-Loop model. The results showed decreased degradation rates of the Zn-Cu-Fe alloy after incorporating FBS into the medium. Also, the alloy exhibited acceptable toxicity towards RAW264.7, HUVEC, and MC3T3-E1 cells. Regarding hemocompatibility, the alloy did not significantly alter erythrocyte, platelet, and leukocyte counts, while the coagulation and complement systems were activated. This study demonstrated the predictable in vitro degradation behavior, acceptable cytotoxicity, and appropriate hemocompatibility of Zn-Cu-Fe alloy; therefore, it might be a candidate biomaterial for craniomaxillofacial implants.

Trace element homeostasis in the neurological system after SARS-CoV-2 infection: Insight into potential biochemical mechanisms

BACKGROUND

Several studies have suggested that COVID-19 is a systemic disease that can affect several organs, including the brain. In the brain, specifically, viral infection can cause dyshomeostasis of some trace elements that promote complex biochemical reactions in specialized neurological functions.

OBJECTIVE

Understand the neurovirulence of SARS-CoV-2 and the relationship between trace elements and neurological disorders after infection, and provide new insights on the drug development for the treatment of SARS-CoV-2 infections.

METHODS

The main databases were used to search studies published up September 2021, focusing on the role of trace elements during viral infection and on the correct functioning of the brain.

RESULTS

The imbalance of important trace elements can accelerate SARS-CoV-2 neurovirulence and increase the neurotoxicity since many neurological processes can be associated with the homeostasis of metal and metalloproteins. Some studies involving animals and humans have suggested the synapse as a vulnerable region of the brain to neurological disorders after viral infection. Considering the combined evidence, some mechanisms have been suggested to understand the relationship between neurological disorders and imbalance of trace elements in the brain after viral infection.

CONCLUSION

Trace elements play important roles in viral infections, such as helping to activate immune cells, produce antibodies, and inhibit virus replication. However, the relationship between trace elements and virus infections is complex since the specific functions of several elements remain largely undefined. Therefore, there is still a lot to be explored to understand the biochemical mechanisms involved between trace elements and viral infections, especially in the brain.

Regulation of zinc-dependent enzymes by metal carrier proteins

Zn²⁺ ions are essential in many physiological processes, including enzyme catalysis, protein structural stabilization, and the regulation of many proteins. The affinities of proteins for Zn²⁺ ions span several orders of magnitude, with catalytic Zn²⁺ ions generally held more tightly than structural or regulatory ones. Metal carrier proteins, most of which are not specific for Zn²⁺, bind these ions with a broad range of affinities that overlap those of catalytic, structural, and regulatory Zn²⁺ ions and are thought to be responsible for distributing the metal through most cells, tissues, and fluid compartments. While little is known about how many proteins obtain or release these ions, there is now considerable experimental evidence suggesting that metal carrier proteins may be responsible for transferring metals to and from some Zn²⁺-dependent proteins, thus serving as a major regulatory factor for them. In this review, the biological roles of Zn²⁺ and structures of Zn²⁺ binding sites are examined, and experimental evidence demonstrating the direct participation of metal carrier proteins in enzyme regulation is discussed. Mechanisms of metal ion transfer are also offered, and the potential physiological significance of this phenomenon is explored.

Selected transgenic murine models of human autoimmune liver diseases

Murine models of human diseases are of outmost importance for both studying molecular mechanisms driving their development and testing new treatment strategies. In this review, we first discuss the etiology and risk factors for autoimmune liver disease, including primary biliary cholangitis, autoimmune hepatitis and primary sclerosing cholangitis. Second, we highlight important features of murine transgenic models that make them useful for basic scientists, drug developers and clinical researchers. Next, a brief description of each disease is followed by the characterization of selected animal models.

Cytoplasmic zinc promotes IL-1β production by monocytes and macrophages through mTORC1-induced glycolysis in rheumatoid arthritis

[Figure: see text].

Serum zinc levels in pediatric patients with COVID-19

Zinc has potent immunoregulatory and antiviral effects that are critical for growth, immunity, and neurologic development. The aim of this study was to determine the clinical significance of serum zinc levels in pediatric patients with COVID-19 and to demonstrate its association with disease severity. This prospective observational study was conducted between August 3 and November 15, 2020, in pediatric patients aged 1 month to 18 years with confirmed COVID-19 using reverse transcription-polymerase chain reaction. We defined a control group whose serum zinc levels were determined 1 year ago at the same time as those of patients with COVID-19. We used 70 μg/dL as the cut-off zinc value to define zinc deficiency. Statistical analyses were performed using the SPSS for Windows statistics package program. One hundred children with confirmed COVID-19 and 269 children in the control group participated in the study. The median age was 13.3 (IQR: 8-15.4) years in patients with confirmed COVID-19, 11 patients had low serum zinc levels, and 89 patients had normal serum zinc levels. Patients in the group with low zinc levels had a significantly higher hospitalization rate than the group with normal zinc levels (5 (45.5%) and 10 patients (11.2%), respectively) (p = 0.011). The median serum zinc level in patients with COVID-19 was 88.5 mcg/dL (IQR 77.2-100), which was significantly lower than the median level in the control group, which was 98 mcg/dL (IQR 84-111) (p = 0.001). There was no association between the severity of COVID-19 and the serum zinc levels of the children.

CONCLUSION

Serum zinc levels may be influenced by many factors such as fasting status, diurnal variation, exercise, and sex, and may give an impression of the zinc status of the population rather than reflecting the individual. The fact that the incidence of hospitalization was significantly higher in patients with both COVID-19 and low serum zinc levels suggests that these patients require a detailed assessment of their living environment.

WHAT IS KNOWN

• Serum zinc levels have been found to be low in adult patients diagnosed with COVID-19. • There was a correlation between the severity of COVID-19 and serum zinc levels in adults.

WHAT IS NEW

• Children with low serum zinc levels were found to have a higher number of hospitalizations. • No association was found between the severity of COVID-19 disease and serum zinc levels in children.

Comparison of Oxidative and Hypoxic Stress Responsive Genes from Meta-Analysis of Public Transcriptomes

Analysis of RNA-sequencing (RNA-seq) data is an effective means to analyze the gene expression levels under specific conditions and discover new biological knowledge. More than 74,000 experimental series with RNA-seq have been stored in public databases as of 20 October 2021. Since this huge amount of expression data accumulated from past studies is a promising source of new biological insights, we focused on a meta-analysis of 1783 runs of RNA-seq data under the conditions of two types of stressors: oxidative stress (OS) and hypoxia. The collected RNA-seq data of OS were organized as the OS dataset to retrieve and analyze differentially expressed genes (DEGs). The OS-induced DEGs were compared with the hypoxia-induced DEGs retrieved from a previous study. The results from the meta-analysis of OS transcriptomes revealed two genes, CRIP1 and CRIP3, which were particularly downregulated, suggesting a relationship between OS and zinc homeostasis. The comparison between meta-analysis of OS and hypoxia showed that several genes were differentially expressed under both stress conditions, and it was inferred that the downregulation of cell cycle-related genes is a mutual biological process in both OS and hypoxia.

Metal transporter Slc30a1 controls pharyngeal neural crest differentiation via the zinc-Snai2-Jag1 cascade

The pharyngeal arch (PA) is a neural crest (NC)-derived organ that is transiently developed during embryogenesis and is required for the subsequent development of various tissues. However, the role of zinc during PA differentiation from NC progenitor cells is unknown. Here, we found that the metal transporters Slc30a1a and Slc30a1b mediate zinc homeostasis during PA differentiation. Slc30a1-deficient zebrafish develop zinc accumulation in NC cells, with increased expression of stemness markers and PA dorsal genes, and SMART-seq analyses revealed that the genes snai2 and jag1b may serve as downstream targets. Furthermore, functional studies showed that knocking down either snai2 or jag1b rescues PA development in Slc30a1-deficient zebrafish. Notably, we identified the double zinc-finger domain in the transcription factor Snai2 as a zinc-responsive element that regulates jag1b expression. Our findings indicate that the Slc30a1/zinc-snai2-jag1b axis is an essential regulatory network controlling PA differentiation, shedding new light on the function of zinc homeostasis in maintaining NC cell stemness and multipotency in vertebrates.

The effect of vitamin D, magnesium and zinc supplements on interferon signaling pathways and their relationship to control SARS-CoV-2 infection

The concern of today's communities is to find a way to prevent or treat COVID-19 and reduce its symptoms in the patients. However, the genetic mutations and more resistant strains of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerge; the designed vaccines and adjuvant therapies would potentially control the symptoms and severity of COVID-19. The most important complication of this viral infection is acute respiratory distress syndrome, which occurs due to the infiltration of leukocytes into the alveoli and the raised cytokine storm. Interferons, as a cytokine family in the host, play an important role in the immune-related antiviral defense and have been considered in the treatment protocols of COVID-19. In addition, it has been indicated that some nutrients, including vitamin D, magnesium and zinc are essential in the modulation of the immune system and interferon (IFN) signaling pathway. Several recent studies have investigated the treatment effect of vitamin D on COVID-19 and reported the association between optimal levels of this vitamin and reduced disease risk. In the present study, the synergistic action of vitamin D, magnesium and zinc in IFN signaling is discussed as a treatment option for COVID-19 involvement.

Network-Based Approaches Reveal Potential Therapeutic Targets for Host-Directed Antileishmanial Therapy Driving Drug Repurposing

Leishmania parasites are the causal agent of leishmaniasis, an endemic disease in more than 90 countries worldwide. Over the years, traditional approaches focused on the parasite when developing treatments against leishmaniasis. Despite numerous attempts, there is not yet a universal treatment, and those available have allowed for the appearance of resistance. Here, we propose and follow a host-directed approach that aims to overcome the current lack of treatment. Our approach identifies potential therapeutic targets in the host cell and proposes known drug interactions aiming to improve the immune response and to block the host machinery necessary for the survival of the parasite. We started analyzing transcription factor regulatory networks of macrophages infected with Leishmania major. Next, based on the regulatory dynamics of the infection and available gene expression profiles, we selected potential therapeutic target proteins. The function of these proteins was then analyzed following a multilayered network scheme in which we combined information on metabolic pathways with known drugs that have a direct connection with the activity carried out by these proteins. Using our approach, we were able to identify five host protein-coding gene products that are potential therapeutic targets for treating leishmaniasis. Moreover, from the 11 drugs known to interact with the function performed by these proteins, 3 have already been tested against this parasite, verifying in this way our novel methodology. More importantly, the remaining eight drugs previously employed to treat other diseases, remain as promising yet-untested antileishmanial therapies. IMPORTANCE This work opens a new path to fight parasites by targeting host molecular functions by repurposing available and approved drugs. We created a novel approach to identify key proteins involved in any biological process by combining gene regulatory networks and expression profiles. Once proteins have been selected, our approach employs a multilayered network methodology that relates proteins to functions to drugs that alter these functions. By applying our novel approach to macrophages during the Leishmania infection process, we both validated our work and found eight drugs already approved for use in humans that to the best of our knowledge were never employed to treat leishmaniasis, rendering our work as a new tool in the box available to the scientific community fighting parasites.

Global Analysis of the Zinc Homeostasis Network in Pseudomonas aeruginosa and Its Gene Expression Dynamics

Zinc is one of the most important trace elements for life and its deficiency, like its excess, can be fatal. In the bacterial opportunistic pathogen Pseudomonas aeruginosa, Zn homeostasis is not only required for survival, but also for virulence and antibiotic resistance. Thus, the bacterium possesses multiple Zn import/export/storage systems. In this work, we determine the expression dynamics of the entire P. aeruginosa Zn homeostasis network at both transcript and protein levels. Precisely, we followed the switch from a Zn-deficient environment, mimicking the initial immune strategy to counteract bacterial infections, to a Zn-rich environment, representing the phagocyte metal boost used to eliminate an engulfed pathogen. Thanks to the use of the NanoString technology, we timed the global silencing of Zn import systems and the orchestrated induction of Zn export systems. We show that the induction of Zn export systems is hierarchically organized as a function of their impact on Zn homeostasis. Moreover, we identify PA2807 as a novel Zn resistance component in P. aeruginosa and highlight new regulatory links among Zn-homeostasis systems. Altogether, this work unveils a sophisticated and adaptive homeostasis network, which complexity is key in determining a pathogen spread in the environment and during host-colonization.

Intein Inhibitors as Novel Antimicrobials: Protein Splicing in Human Pathogens, Screening Methods, and Off-Target Considerations

Protein splicing is a post-translational process by which an intervening polypeptide, or intein, catalyzes its own removal from the flanking polypeptides, or exteins, concomitant with extein ligation. Although inteins are highly abundant in the microbial world, including within several human pathogens, they are absent in the genomes of metazoans. As protein splicing is required to permit function of essential proteins within pathogens, inteins represent attractive antimicrobial targets. Here we review key proteins interrupted by inteins in pathogenic mycobacteria and fungi, exciting discoveries that provide proof of concept that intein activity can be inhibited and that this inhibition has an effect on the host organism's fitness, and bioanalytical methods that have been used to screen for intein activity. We also consider potential off-target inhibition of hedgehog signaling, given the similarity in structure and function of inteins and hedgehog autoprocessing domains.

Characterization of Global Gene Expression, Regulation of Metal Ions, and Infection Outcomes in Immune-Competent 129S6 Mouse Macrophages

Nutritional immunity involves cellular and physiological responses to invading pathogens, such as limiting iron, increasing exposure to bactericidal copper, and altering zinc to restrict the growth of pathogens. Here, we examine infection of bone marrow-derived macrophages from 129S6/SvEvTac mice by Salmonella enterica serovar Typhimurium. The 129S6/SvEvTac mice possess a functional Slc11a1 (Nramp-1), a phagosomal transporter of divalent cations that plays an important role in modulating metal availability to the pathogen. We carried out global RNA sequencing upon treatment with live or heat-killed Salmonella at 2 h and 18 h postinfection and observed widespread changes in metal transport, metal-dependent genes, and metal homeostasis genes, suggesting significant remodeling of iron, copper, and zinc availability by host cells. Changes in host cell gene expression suggest infection increases cytosolic zinc while simultaneously limiting zinc within the phagosome. Using a genetically encoded sensor, we demonstrate that cytosolic labile zinc increases 45-fold at 12 h postinfection. Further, manipulation of zinc in the medium alters bacterial clearance and replication, with zinc depletion inhibiting both processes. Comparing the transcriptomic changes to published data on infection of C57BL/6 macrophages revealed notable differences in metal regulation and the global immune response. Our results reveal that 129S6 macrophages represent a distinct model system compared to C57BL/6 macrophages. Further, our results indicate that manipulation of zinc at the host-pathogen interface is more nuanced than that of iron or copper. The 129S6 macrophages leverage intricate means of manipulating zinc availability and distribution to limit the pathogen's access to zinc, while simultaneously ensuring sufficient zinc to support the immune response.

Immunomodulatory bioactive glasses for tissue regeneration

The regulatory functions of the immune response in tissue healing, repair, and regeneration have been evidenced in the last decade. Immune cells play central roles in immune responses toward inducing favorable tissue regenerative processes. Modulating and controlling the immune cell responses (particularly macrophages) is an emerging approach to enhance tissue regeneration. Bioactive glasses (BGs) are multifunctional materials exhibiting osteogenic, angiogenic, and antibacterial properties, being increasingly investigated for various tissue regeneration scenarios, including bone regeneration and wound healing. On the other hand, the immunomodulatory effects of BGs in relation to regenerating tissues have started to be understood, and key knowledge is emerging. This is the first review article summarizing the immunomodulatory effects of BGs for tissue repair and regeneration. The immune response to BGs is firstly introduced, discussing potential mechanisms regarding the immunomodulation effects induced by BGs. Moreover, the interactions between the immune cells involved in the immunomodulation process and BGs (dissolution products) are summarized in detail. Particularly, a well-regulated and timely switch of macrophage phenotype from pro-inflammatory to anti-inflammatory is crucial to constructive tissue regeneration through modulating osteogenesis, osteoclastogenesis, and angiogenesis. The influence of BG characteristics on macrophage responses is discussed. We highlight the strategies employed to harness macrophage responses for enhanced tissue regeneration, including the incorporation of active ions, surface functionalization, and controlled release of immunomodulatory molecules. Finally, we conclude with our perspectives on future research challenges and directions in the emerging field of immunomodulatory BGs for tissue regeneration. STATEMENT OF SIGNIFICANCE: Immunomodulatory effects of bioactive glasses (BGs) in relation to bone regeneration and wound healing have started to be understood. We summarize those studies which have focused on immunomodulatory BGs for tissue regeneration. We first introduce the potential mechanisms of the immunomodulation effects induced by BGs. Interactions between the cells involved in immunomodulation processes and BGs (and their dissolution products, biologically active ions) are elaborated. We highlight the strategies employed to modulate macrophage responses for enhancing tissue regeneration, including incorporation of active ions, surface functionalization, and controlled release of immunomodulatory agents. This is the first review article summarizing and outlining the immunomodulatory effects of BGs for tissue regeneration. We anticipate that increasing research efforts will start to emerge in the area of immunomodulatory BGs.

Comparative Transcriptome Analysis in Monocyte-Derived Macrophages of Asymptomatic GBA Mutation Carriers and Patients with GBA-Associated Parkinson's Disease

Mutations of the GBA gene, encoding for lysosomal enzyme glucocerebrosidase (GCase), are the greatest genetic risk factor for Parkinson’s disease (PD) with frequency between 5% and 20% across the world. N370S and L444P are the two most common mutations in the GBA gene. PD carriers of severe mutation L444P in the GBA gene is characterized by the earlier age at onset compared to N370S. Not every carrier of GBA mutations develop PD during one’s lifetime. In the current study we aimed to find common gene expression signatures in PD associated with mutation in the GBA gene (GBA-PD) using RNA-seq. We compared transcriptome of monocyte-derived macrophages of 5 patients with GBA-PD (4 L444P/N, 1 N370S/N) and 4 asymptomatic GBA mutation carriers (GBA-carriers) (3 L444P/N, 1 N370S/N) and 4 controls. We also conducted comparative transcriptome analysis for L444P/N only GBA-PD patients and GBA-carriers. Revealed deregulated genes in GBA-PD independently of GBA mutations (L444P or N370S) were involved in immune response, neuronal function. We found upregulated pathway associated with zinc metabolism in L444P/N GBA-PD patients. The potential important role of DUSP1 in the pathogenesis of GBA-PD was suggested.

Exosomes derived from macrophages upon Zn ion stimulation promote osteoblast and endothelial cell functions

Osteogenesis and angiogenesis are both important for implant osseointegration, which can be tailored by immunomodulation of macrophages. Zn, a novel biodegradable material, can modulate macrophage functions in its ionic form. However, whether macrophage-derived exosomes, novel carriers of intracellular communication, participate in the process is still unclear. The present work shows that Zn ions in the concentration range of 0-100 μM have no significant influence on macrophage viability, proliferation, morphology, and secretion amount of exosomes, but generally downregulate the gene expression of both M1 and M2 markers. The exosomes can be ingested continuously by osteoblasts and endothelial cells. The osteoblasts show the highest alkaline phosphatase activity after ingesting the exosomes derived from macrophages upon 4 μM Zn ion stimulation. In contrast, the endothelial cells migrate the furthest distance after ingesting the exosomes upon 20 μM Zn ion stimulation. These results indicate that Zn ions may vary the composition of macrophage-derived exosomes, which in turn affects the osteogenesis and angiogenesis. These findings are meaningful for the surface design of immunomodulatory biomaterials from the perspective of macrophage-derived exosomes.

Dysregulation of metallothionein and zinc aggravates periodontal diseases

BACKGROUND

Periodontitis (PD) is a multifaceted inflammatory disease connected to bacterial infection that results in the destruction of tooth supporting structures and eventually tooth loss. Given their involvement in infection and inflammation, both metallothionein (MT) and zinc (Zn) might play vital roles in the development and progression of PD. More specifically, both MT and Zn are heavily involved in regulating immune functions, controlling bacterial infection, balancing inflammatory responses, and reducing oxidative stress, all of which are associated with the pathogenesis of PD.

OBJECTIVE

This review paper will explore the physiological functions of MT and Zn and hypothesise how dysregulation could negatively affect periodontal health, leading to PD.

FINDINGS

Bacterial lipopolysaccharide (LPS) derived from periodontal pathogens, namely P. gingivalis initiates the acute phase response, thus upregulating the expression of MT which leads to the subsequent deficiency of Zn, a hallmark of periodontal disease. This deficiency leads to ineffective NETosis, increases the permeability of the gingival epithelium, and disrupts the humoral immune response, collectively contributing to PD. In addition, the presence of LPS in Zn deficient conditions favours M1 macrophage polarisation and maturation of dendritic cells, and also inhibits the anti-inflammatory activity of regulatory T cells. Collectively, these observations could theoretically give rise to the chronic inflammation seen in PD.

CONCLUSION

A disrupted MT and Zn homeostasis is expected to exert an adverse impact on periodontal health and contribute to the development and progression of PD.

Regulatory Role of Zinc in Immune Cell Signaling

Zinc is an essential micronutrient with crucial roles in multiple facets of biological processes. Dysregulated zinc homeostasis impairs overall immune function and resultantly increases susceptibility to infection. Clinically, zinc supplementation is practiced for treatment of several infectious diseases, such as diarrhea and malaria. Recent focus on zinc as a beneficial element for immune system support has resulted in investigation of the immunomodulatory roles of zinc in a variety of immune cells. Besides its classical role as a cofactor that regulates the structural function of thousands of proteins, accumulating evidence suggests that zinc also acts, in a manner similar to calcium, as an ionic regulator of immune responses via participation as an intracellular messenger in signaling pathways. In this review, we focus on the role of zinc as a signaling molecule in major pathways such as those downstream of Toll-like receptors-, T cell receptor-, and cytokine-mediated signal transduction that regulate the activity and function of monocytes/macrophages and T cells, principal players in the innate and adaptive immune systems.

Light-controlled growth factors release on tetrapodal ZnO-incorporated 3D-printed hydrogels for developing smart wound scaffold

Advanced wound scaffolds that integrate active substances to treat chronic wounds have gained significant recent attention. While wound scaffolds and advanced functionalities have previously been incorporated into one medical device, the wirelessly triggered release of active substances has remained the focus of many research endeavors. To combine multiple functions including light-triggered activation, anti-septic, angiogenic, and moisturizing properties, we have developed a 3D printed hydrogel patch encapsulating vascular endothelial growth factor (VEGF) decorated with photoactive and antibacterial tetrapodal zinc oxide (t-ZnO) microparticles. To achieve the smart release of VEGF, t-ZnO was modified by chemical treatment and activated through UV/visible light exposure. This process would also make the surface rough and improve protein adhesion. The elastic modulus and degradation behavior of the composite hydrogels, which must match the wound healing process, were adjusted by changing t-ZnO concentrations. The t-ZnO-laden composite hydrogels can be printed with any desired micropattern to potentially create a modular elution of various growth factors. The VEGF decorated t-ZnO-laden hydrogel patches showed low cytotoxicity and improved angiogenic properties while maintaining antibacterial functions in vitro. In vivo tests showed promising results for the printed wound patches, with less immunogenicity and enhanced wound healing.