Targeting Biometals in Alzheimer's Disease with Metal Chelating Agents Including Coumarin Derivatives.

Numerous physiological processes happening in the human body, including cerebral development and function, require the participation of biometal ions such as iron, copper, and zinc. Their dyshomeostasis may, however, contribute to the onset of Alzheimer's disease (AD) and potentially other neurodegenerative diseases. Chelation of biometal ions is therefore a therapeutic strategy against AD. This review provides a survey of natural and synthetic chelating agents that are or could potentially be used to target the metal hypothesis of AD. Since metal dyshomeostasis is not the only pathological aspect of AD, and the nature of this disorder is very complex and multifactiorial, the most efficient therapeutics should target as many neurotoxic factors as possible. Various coumarin derivatives match this description and apart from being able to chelate metal ions, they exhibit the capacity to inhibit cholinesterases (ChEs) and monoamine oxidase B (MAO-B) while also possessing antioxidant, anti-inflammatory, and numerous other beneficial effects. Compounds based on the coumarin scaffold therefore represent a desirable class of anti-AD therapeutics.

Towards Clinical Development of Scandium Radioisotope Complexes for Use in Nuclear Medicine: Encouraging Prospects with the Chelator 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic Acid (DOTA) and Its Analogues.

Scandium (Sc) isotopes have recently attracted significant attention in the search for new radionuclides with potential uses in personalized medicine, especially in the treatment of specific cancer patient categories. In particular, Sc-43 and Sc-44, as positron emitters with a satisfactory half-life (3.9 and 4.0 h, respectively), are ideal for cancer diagnosis via Positron Emission Tomography (PET). On the other hand, Sc-47, as an emitter of beta particles and low gamma radiation, may be used as a therapeutic radionuclide, which also allows Single-Photon Emission Computed Tomography (SPECT) imaging. As these scandium isotopes follow the same biological pathway and chemical reactivity, they appear to fit perfectly into the "theranostic pair" concept. A step-by-step description, initiating from the moment of scandium isotope production and leading up to their preclinical and clinical trial applications, is presented. Recent developments related to the nuclear reactions selected and employed to produce the radionuclides Sc-43, Sc-44, and Sc-47, the chemical processing of these isotopes and the main target recovery methods are also included. Furthermore, the radiolabeling of the leading chelator, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), and its structural analogues with scandium is also discussed and the advantages and disadvantages of scandium complexation are evaluated. Finally, a review of the preclinical studies and clinical trials involving scandium, as well as future challenges for its clinical uses and applications, are presented.

The impact of chelating compounds on Cu2+, Fe2+/3+, and Zn2+ ions in Alzheimer's disease treatment.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid - ß extracellular plaques and tau interfibrillar tangles, leading to memory loss, cognitive decline, and behavioral changes. With dementia posing a growing global health concern, there is an urgent need for comprehensive strategies to address its challenges. The economic burden of dementia is projected to rise significantly, emphasizing the necessity for collaborative efforts in research and healthcare. In the United States alone, millions are affected by AD, with prevalence increasing with age and even affecting younger individuals. The complexity of AD involves intricate biological processes, including the aggregation of amyloid beta, oxidative stress, and metal ion dysregulation. Metal ions, particularly those from copper, iron, and zinc, play pivotal roles in AD pathology, influencing Aß deposition and tau protein accumulation. Current treatments offer symptomatic relief but do not address the underlying disease mechanisms. This paper explores the potential of various chelating compounds to target metal ions involved in AD pathology. N-acylhydrazones, morpholine, chrysin, quinoline, oxindole, cyclam, catechol-based, and quinazolinone-based derivatives show promising chelation activity and therapeutic effects. Metal chelation therapy offers a targeted approach to AD treatment by addressing the core pathology. By selectively binding to metal ions implicated in disease progression, chelators may minimize side effects associated with broad-spectrum treatments. Additionally, chelators may offer neuroprotective effects beyond metal binding, further enhancing their therapeutic potential. Overall, metal chelation therapy presents a promising strategy in combating AD, with the potential to significantly impact disease progression and improve patient outcomes.

Relapse following withdrawal of D-penicillamine from combination (D-penicillamine + zinc) therapy in hepatic Wilson disease.

OBJECTIVES: Long-term D-penicillamine (D-pen) therapy in Wilson disease (WD) has numerous adverse effects which advocates its withdrawal, but with an inherent risk of relapse. This prospective observational study was conducted with the objective of evaluating incidence of relapse following withdrawal of D-pen from combination (D-pen + zinc) therapy in maintenance phase of previously symptomatic hepatic WD. METHODS: Hepatic WD patients <18 years of age and on combination therapy for >2 years with 6 months of biochemical remission were included. Biochemical remission was defined as achievement of (i) aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤1.5 times upper limit of normal (ULN), (ii) serum albumin >3.5 g/dL, international normalized ratio (INR) <1.5 and (iii) 24-h urinary copper excretion (UCE) <500 mcg/day, nonceruloplasmin-bound-copper (NCC) <15 mcg/dL. After D-pen withdrawal, monthly liver function test (LFT) and INR and 3 monthly UCE and NCC were done till 1 year or relapse (elevation of AST/ALT/both >2 times ULN or total bilirubin >2 mg/dL), whichever occurred earlier. RESULTS: Forty-five patients enrolled with median combination therapy duration of 36 months. Sixty percent of them had their index presentation as decompensated cirrhosis. Fourteen patients (31.8%) relapsed (cumulative incidence: 4 at 3 months, 11 at 6 months, and 14 at 12 months after D-pen discontinuation). All relapsers had index presentation as decompensated cirrhosis. On Cox-regression, ALT at D-pen withdrawal was an independent predictor of relapse (hazard ratio [HR]: 1.077, 95% confidence interval [CI]: 1.014-1.145, p = 0.017) with area under the receiver operating characteristic (AUROC) of 0.860. ALT ≥40 U/L predicted risk of relapse with 85.7% sensitivity, 70.9% specificity. CONCLUSION: Incidence of relapse after withdrawal of D-pen from combination therapy is 31.8% in hepatic WD. ALT ≥40 U/L, at the time of D-pen stoppage, predicts future relapse.

Navigating through the coordination preferences of heavy alkaline earth metals: Laying the foundations for 223Ra- and 131/135mBa-based targeted alpha therapy and theranostics of cancer.

The clinical success of [223Ra]RaCl2 (Xofigo®) for the palliative treatment of bone metastases in patients with prostate cancer has highlighted the therapeutic potential of α-particle emission. Expanding the applicability of radium-223 in Targeted Alpha Therapy of non-osseous tumors is followed up with significant interest, as it holds the potential to unveil novel treatment options in the comprehensive management of cancer. Moreover, the use of barium radionuclides, like barium-131 and -135m, is still unfamiliar in nuclear medicine applications, although they can be considered as radium-223 surrogates for imaging purposes. Enabling these applications requires the establishment of chelators able to form stable complexes with radium and barium radionuclides. Until now, only a limited number of ligands have been suggested and these molecules have been primarily inspired by existing structures known for their ability to complex large metal cations. However, a systematic inspection of chelators specifically tailored to Ra2+ and Ba2+ has yet to be conducted. This work delves into a comprehensive investigation of a series of small organic ligands, aiming to unveil the coordination preferences of both radium-223 and barium-131/135m. Electronic binding energies of both metal cations to each ligand were theoretically computed via Density Functional Theory calculations (COSMO-ZORA-PBE-D3/TZ2P), while thermodynamic stability constants were experimentally determined for Ba2+-ligand complexes by potentiometry, NMR and UV-Vis spectroscopies. The outcomes revealed malonate, 2-hydroxypyridine 1-oxide and picolinate as the most favorable building blocks to design multidentate chelators. These findings serve as foundation guidelines, propelling the development of cutting-edge radium-223- and barium-131/135m-based radiopharmaceuticals for Targeted Alpha Therapy and theranostics of cancer.

Wilson disease: the diagnostic challenge and treatment outcomes in a series of 262 cases.

BACKGROUND: Wilson disease (WD) is an autosomal recessive disorder that leads to organ toxicity due to copper overload. Early diagnosis is complicated by the rarity and diversity of manifestations. OBJECTIVE: To describe the diagnostic features and response to treatment in our cohort of WD patients. METHODS: This was a retrospective analysis of 262 WD patients stratified by clinical presentation, complementary exams, ATP7B genotyping, and response to treatment. RESULTS: Symptoms occurred at an average age of 17.4 (7-49) years, and patients were followed up for an average of 9.6 (0-45) years. Patients presented mainly with hepatic (36.3%), neurologic (34.7%), and neuropsychiatric (8.3%) forms. Other presentations were hematologic, renal, or musculoskeletal, and 16.8% of the patients were asymptomatic. Kayser-Fleischer rings occurred in 78.3% of the patients, hypoceruloplasminemia in 98.3%, and elevated cupruria/24h in 73.0%, with an increase after D-penicillamine in 54.0%. Mutations of the ATP7B gene were detected in 84.4% of alleles. Brain magnetic resonance imaging showed abnormalities in the basal ganglia in 77.7% of patients. D-penicillamine was the first choice in 93.6% of the 245 patients, and 21.1% of these patients were switched due to adverse effects. The second-line therapies were zinc and trientine. The therapeutic response did not differ significantly between the drugs (p = 0.2). Nine patients underwent liver transplantation and 82 died. CONCLUSION: Wilson disease is diagnosed at a late stage, and therapeutic options are limited. In people under 40 years of age with compatible manifestations, WD could be considered earlier in the differential diagnosis. There is a need to include ATP7B genotyping and therapeutic alternatives in clinical practice.

ANTECEDENTES: A doença de Wilson (DW) é um distúrbio autossômico recessivo caracterizado por acúmulo de cobre lesivo aos órgãos. O diagnóstico precoce é dificultado pela raridade e diversidade de apresentações. OBJETIVO: Descrever características ao diagnóstico e resposta ao tratamento em uma coorte de DW. MéTODOS: Análise retrospectiva de 262 casos de DW quanto à apresentação clínica, exames complementares, genotipagem e resposta ao tratamento. RESULTADOS: Os sintomas surgiram em uma média aos 17,4 (7­49) anos, e os pacientes foram acompanhados por uma média de 9,6 (0­45) anos. Os pacientes apresentaram principalmente formas hepáticas (36,3%), neurológicas (34,7%) e neuropsiquiátricas (8,3%). Outras apresentações foram hematológicas, renais e musculoesqueléticas. Apenas 16,8% eram assintomáticos. Anéis de Kayser-Fleischer ocorreram em 78,3% dos pacientes, hipoceruloplasminemia em 98,3%, e cuprúria elevada/24h em 73,0%, com aumento após D-penicilamina em 54,0%. Mutações do gene ATP7B foram detectadas em 84,4% dos alelos pesquisados. A ressonância magnética cerebral mostrou alterações em gânglios da base em 77,7% dos pacientes. O tratamento com D-penicilamina foi a escolha inicial em 93,6% dos 245 casos e foi trocado em 21,1% devido a efeitos adversos. Terapias de segunda linha foram zinco e trientina. A resposta terapêutica não diferiu significativamente entre os medicamentos (p = 0,2). Nove pacientes receberam transplante hepático e 82 faleceram. CONCLUSãO: O diagnóstico da DW ainda ocorre em estágios tardios, e as opções terapêuticas são limitadas. A DW deve ser considerada precocemente no diagnóstico diferencial de pessoas com menos de 40 anos com manifestações compatíveis. É necessário incorporar na prática clínica a genotipagem do ATP7B e alternativas terapêuticas à penicilamina.

Heavy metal poisoning caused by Chinese folk remedies in psoriasis patients: a retrospective analysis.

Psoriasis, characterized as a chronic relapsing disease with a protracted course, often drives patients to seek relief through Chinese folk remedies (CFR). Nonetheless, the complex compositions of these remedies frequently result in unintended adverse effects, notably various types of heavy metal poisoning. Our study involved an exhaustive collection and analysis of clinical data from psoriasis patients who developed heavy metal poisoning due to CFR usage, admitted to Beijing Chao-Yang Hospital from January 2011 to October 2023. Our analysis identified 44 cases of mercury poisoning, 17 of lead poisoning, 21 of arsenic poisoning, and 4 instances of mixed heavy metal poisoning. The folk remedies used ranged from fumigation and inhalation to skin application and oral administration. Distinct pathogenic characteristics were observed in each poisoning type. After treatment with metal chelating agents, all patients experienced a reduction in heavy metal levels in their bodies, accompanied by varying degrees of symptom alleviation. This study underscores the vital necessity of opting for formal, medically approved treatments for psoriasis, thereby avoiding the hazardous consequences of unregulated folk remedies that may lead to severe heavy metal poisoning.

The impact of accessibility to non-calcium-based phosphate binders and calcimimetics on mineral outcomes in patients receiving maintenance hemodialysis: A 10-year retrospective analysis of real-world data.

INTRODUCTION: Hyperphosphatemia and hyperparathyroidism are common in end-stage kidney disease and are associated with poor outcomes. In addition to adequate dialysis, medications are usually required for optimum control of serum phosphate and parathyroid hormone (PTH) levels. The use of calcium-based phosphate binders (CBPBs) and active vitamin D is associated with an increase in serum calcium and worsening vascular calcification. To overcome these limitations, non-calcium-based phosphate binders (NCBPBs) and calcimimetics have been developed. However, the coverage for these new medications remains limited in several parts of the world due to the lack of patient-level outcome data and cost. The present study examined the differences in mineral outcomes between two main categories of healthcare programs that provided different coverage for medications used to control mineral and bone disorders (MBD). The Social Security/Universal Coverage (SS/UC) program covered only CBPBs and active vitamin D, whereas the Civil Servant/State Enterprise (CS/SE) program provided coverage of CBPBs, active vitamin D, NCBPBs, and calcimimetics. METHODS: This 10-year retrospective cohort study examined the differences in mineral outcomes between two healthcare programs in maintenance hemodialysis patients. The differences in serum calcium, phosphate, and PTH levels, as well as the aortic arch calcification score, were analyzed according to dialysis vintage by linear mixed-effects regression analyses. The difference in the composite outcome of severe hyperparathyroidism and parathyroidectomy was analyzed by the Cox-proportional hazard regression model. RESULTS: 714 patients were included in the analyses (full cohort). Of these patients, 563 required at least one type of medication to control MBD (MBD medication subgroup). Serum calcium, phosphate, and the proportions of patients with hypercalcemia and hyperphosphatemia were substantially higher in the SS/UC group compared with the CS/SE group after appropriate adjustments for confounders in both the full cohort and the MBD medication subgroup. These findings were confirmed in propensity-score matched analyses. Higher parathyroid hormone levels and a higher rate of the composite endpoint of severe hyperparathyroidism and parathyroidectomy were also observed in the SS/UC group. A more rapid progression of aortic arch calcification was suggested in the SS/UC group, but between-group changes were not significant. CONCLUSION: Patients under the healthcare program that did not cover the use of NCBPBs and calcimimetics showed higher serum calcium and phosphate levels and a more rapid progression of hyperparathyroidism. The difference in the progression of vascular calcification could not be confirmed in the present study.

Prevalence, Incidence, and Treatment Pattern of Wilson's Disease Using National Health Insurance Data From 2010-2020, Korea.

BACKGROUND: Wilson's disease (WD) is an autosomal recessive disorder in which copper (Cu) accumulates in organs, particularly in the liver and central nervous system. This study aimed to investigate the prevalence, incidence, and treatment patterns of WD patients in Korea. METHODS: National Health Insurance System (NHIS) claims data from 2010 to 2020 were analyzed. patients with WD as a primary or additional diagnosis at least once were identified using the International Classification of Diseases (ICD)-10 disease code E83.0 and a record for a registration program for rare intractable diseases in Korea. RESULTS: The average age- and sex-adjusted prevalence and incidence of WD between 2010 and 2020 were 3.06/100,000 and 0.11/100,000, respectively. The mean age of the patients with newly diagnosed WD was 21.0 ± 15.9 years. Among the 622 WD incident cases during the study period, 19.3% of the patients had liver cirrhosis and 9.2% had received liver transplantation. Psychological and neurological diseases were present in 40.7% and 48.1% of the patients, respectively. Regarding the diagnosis of WD, liver biopsy was performed in only 51.6% of new cases. D-penicillamine, trientine, or zinc were prescribed in 81.5% of the incident cases, and the treatment uptake rates decreased with increasing age. CONCLUSION: The prevalence of WD in Korea is 3.06/100,000 and approximately 1,800 patients use medical services annually. A significant proportion of patients are diagnosed at the cirrhotic stage and not treated with Cu-chelating therapeutics, suggesting the need for early diagnosis and adequate treatment to improve prognosis.

Baseline characteristics including blood and urine metal levels in the Trial to Assess Chelation Therapy 2 (TACT2).

BACKGROUND: The reduction in cardiovascular disease (CVD) events with edetate disodium (EDTA) in the Trial to Assess Chelation Therapy (TACT) suggested that chelation of toxic metals might provide novel opportunities to reduce CVD in patients with diabetes. Lead and cadmium are vasculotoxic metals chelated by EDTA. We present baseline characteristics for participants in TACT2, a randomized, double-masked, placebo-controlled trial designed as a replication of the TACT trial limited to patients with diabetes. METHODS: TACT2 enrolled 1,000 participants with diabetes and prior myocardial infarction, age 50 years or older between September 2016 and December 2020. Among 959 participants with at least one infusion, 933 had blood and/or urine metals measured at the Centers for Diseases Control and Prevention using the same methodology as in the National Health and Nutrition Examination Survey (NHANES). We compared metal levels in TACT2 to a contemporaneous subset of NHANES participants with CVD, diabetes and other inclusion criteria similar to TACT2's participants. RESULTS: At baseline, the median (interquartile range, IQR) age was 67 (60, 72) years, 27% were women, 78% reported white race, mean (SD) BMI was 32.7 (6.6) kg/m2, 4% reported type 1 diabetes, 46.8% were treated with insulin, 22.3% with GLP1-receptor agonists or SGLT-2 inhibitors, 90.2% with aspirin, warfarin or P2Y12 inhibitors, and 86.5% with statins. Blood lead was detectable in all participants; median (IQR) was 9.19 (6.30, 13.9) µg/L. Blood and urine cadmium were detectable in 97% and median (IQR) levels were 0.28 (0.18, 0.43) µg/L and 0.30 (0.18, 0.51) µg/g creatinine, respectively. Metal levels were largely similar to those in the contemporaneous NHANES subset. CONCLUSIONS: TACT2 participants were characterized by high use of medication to treat CVD and diabetes and similar baseline metal levels as in the general US population. TACT2 will determine whether chelation therapy reduces the occurrence of subsequent CVD events in this high-risk population. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov. Identifier: NCT02733185. https://clinicaltrials.gov/study/NCT02733185.

Chronic arsenic poisoning: A sinister cause of peripheral neuropathy in a young couple.

ABSTRACT: Arsenic compounds are colorless and odorless and toxicity can occur either acutely following ingestion of arsenicals with gastrointestinal disturbances or due to chronic exposure usually presenting with dermatologic lesions and peripheral neuropathy. We report a young couple who presented with signs and symptoms of painful sensorimotor peripheral neuropathy in a typical "stocking and glove" pattern. They had raised urinary arsenic levels with normal blood levels and thus, a diagnosis of chronic arsenic poisoning due to contaminated water intake was made after detecting elevated arsenic levels in their home water supply. Both patients underwent chelation therapy with dimercaprol for 14 days and reported subjective and objective improvement in symptoms with the reduction in urinary arsenic levels at the end of therapy.

Re-188 lipiodol in hepatocellular carcinoma with portal vein thrombosis: a pilot study using novel chelating agent N-DEDC and its comparison with (A)HDD.

OBJECTIVE: Hepatocellular carcinoma (HCC) with portal vein thrombosis (PVT) have limited therapeutic options, Re-188 lipiodol transarterial therapy being one of them. We aimed to assess the safety and efficacy of Re-188 lipiodol exclusively in HCC with PVT as well as to compare two chelating agents for the synthesis of Re-188 lipiodol: novel bis-(diethyldithiocarbamato) nitrido (N-DEDC) with existing acetylated 4-hexadecyl 1-2,9,9-tetramethyl-4,7-diaza-1,10-decanethiol [(A)HDD]. METHODS: Patients with radiological diagnosis of HCC with PVT having Eastern Cooperative Oncology Group (ECOG) performance status ≤2 and Child Pugh score (PS) A or B were recruited. Patients received an empirical dose of transarterial Re-188 lipiodol, labelled with (A)HDD or N-DEDC. Radiological response on MRI (modified response evaluation criteria in solid tumors), biochemical response with serum alpha fetoprotein and clinical response with ECOG PS was assessed at three months and survival was estimated at the end of the study. RESULTS: Fifteen therapies were performed in 14 patients with a median age of 62 years (range: 41-70 years). Eight therapies were with Re-188 (A)HDD lipiodol and seven with Re-188 N-DEDC lipiodol. Overall mean injected dose was 2.6 ±â€…0.37 GBq. Radiological objective response rate was 31% and disease control rate was 85%. Mean overall survival was 14.21 months and mean progression free survival was 10.23 months. Percentage survival assessed at 3, 6 and 9 months was 93%, 64% and 57%, respectively. Safety parameters, response and survival outcome were comparable for (A)HDD and N-DEDC groups. CONCLUSION: Transarterial Re-188 lipiodol in HCC with PVT is safe and effective in disease control as well as improving survival outcome. Additionally, cost-effective and high-yielding novel agent N-DEDC appears to be a comparable alternative to (A)HDD for the same.

Neurological Deterioration in Wilson's Disease-Types, Etiology, Course, and Management.

Wilson's disease (WD) is an inherited disorder of copper metabolism in which pathological copper accumulation, mainly in the liver and the brain, leads to hepatic and/or neuropsychiatric signs and symptoms. Chelators and zinc salts can successfully induce negative copper balance in many patients; however, neurological deterioration may still be observed. This phenomenon can be divided into: (1) early 'paradoxical' neurological deterioration, which usually develops in the first 6 months of anti-copper treatment and may be commonly related to drug type, or (2) late neurological deterioration, which mostly occurs after 6 months of treatment and is often related either to non-compliance with treatment, overtreatment resulting in copper deficiency, or adverse drug reactions. Another explanation, especially for early neurological deterioration, is natural WD progression, which can be difficult to differentiate from drug-related deterioration, but usually leads to a worse outcome. There is still no consensus on how to define neurological deterioration in WD using scales or biomarkers, how to distinguish it from the natural disease progression, its risk factors, and optimal management. This narrative review, based on the current literature, aims to provide definitions, prevalence, pathological mechanisms and factors related to neurological deterioration, and also proposes schemes for diagnosis and treatment.

Cope with copper: From molecular mechanisms of cuproptosis to copper-related kidney diseases.

Cuproptosis has recently been identified as a novel regulatory mechanism of cell death. It is characterized by the accumulation of copper in mitochondria and its binding to acylated proteins. These characteristics lead to the downregulation of iron-sulfur cluster proteins and protein toxicity stress, ultimately resulting in cell death. Cuproptosis is distinct from other types of cell death, including necrosis, apoptosis, ferroptosis, and pyroptosis. Cu induces oxidative stress damage, protein acylation, and the oligomerization of acylated TCA cycle proteins. These processes lead to the downregulation of iron-sulfur cluster proteins and protein toxicity stress, disrupting cellular Cu homeostasis, and causing cell death. Cuproptosis plays a significant role in the development and progression of various kidney diseases such as acute kidney injury, chronic kidney disease, diabetic nephropathy, kidney transplantation, and kidney stones. On the one hand, inducers of cuproptosis, such as disulfiram (DSF), chloroquinolone, and elesclomol facilitate cuproptosis by promoting cell oxidative stress. In contrast, inhibitors of Cu chelators, such as tetraethylenepentamine and tetrathiomolybdate, relieve these diseases by inhibiting apoptosis. To summarize, cuproptosis plays a significant role in the pathogenesis of kidney disease. This review comprehensively discusses the molecular mechanisms underlying cuproptosis and its significance in kidney diseases.

Constructing "smart" chelators by using an activatable prochelator strategy for the treatment of Wilson's disease.

Wilson's disease (WD) is a genetic disorder that primarily leads to the pathological accumulation of copper (Cu) in the liver, causing an abnormal increase in reactive oxygen species (ROS). The prevailing clinical therapy for WD involves lifelong use of Cu chelation drugs to facilitate Cu excretion in patients. However, most available drugs exert severely side-effects due to their non-specific excretion of Cu, unsuitable for long-term use. In this study, we construct a prochelator that enables precise and controlled delivery of Cu chelator drugs to the liver in WD model, circumventing toxic side effects on other organs and normal tissues. This innovative prochelator rapidly releases the chelator and the fluorescent molecule methylene blue (MB) upon activation by ROS highly expressed in the liver of WD. The released chelator coordinates with Cu, efficiently aiding in Cu removal from the body and effectively inhibiting the pathological progression of WD.

Modulation of Metal Homeostasis for Cancer Therapy.

Metal ions such as iron, zinc, copper, manganese, and calcium are essential for normal cellular processes, including DNA synthesis, enzyme activity, cellular signaling, and oxidative stress regulation. When the balance of metal homeostasis is disrupted, it can lead to various pathological conditions, including cancer. Thus, understanding the role of metal homeostasis in cancer has led to the development of anti-tumor strategies that specifically target the metal imbalance. Up to now, diverse small molecule-based chelators, ionophores, metal complexes, and metal-based nanomaterials have been developed to restore the normal balance of metals or exploit the dysregulation for therapeutic purposes. They hold great promise in inhibiting tumor growth, preventing metastasis, and enhancing the effectiveness of existing cancer therapies. In this review, we aim to provide a comprehensive summary of the strategies employed to modulate the homeostasis of iron, zinc, copper, manganese, and calcium for cancer therapy. Their modulation mechanisms for metal homeostasis are succinctly described, and their recent applications in the field of cancer therapy are discussed. At the end, the limitations of these approaches are addressed, and potential avenues for future developments are explored.

A chemical screen identifies structurally diverse metal chelators with activity against the fungal pathogen Candida albicans.

Candida albicans, one of the most prevalent human fungal pathogens, causes diverse diseases extending from superficial infections to deadly systemic mycoses. Currently, only three major classes of antifungal drugs are available to treat systemic infections: azoles, polyenes, and echinocandins. Alarmingly, the efficacy of these antifungals against C. albicans is hindered both by basal tolerance toward the drugs and the development of resistance mechanisms such as alterations of the drug's target, modulation of stress responses, and overexpression of efflux pumps. Thus, the need to identify novel antifungal strategies is dire. To address this challenge, we screened 3,049 structurally-diverse compounds from the Boston University Center for Molecular Discovery (BU-CMD) chemical library against a C. albicans clinical isolate and identified 17 molecules that inhibited C. albicans growth by >80% relative to controls. Among the most potent compounds were CMLD013360, CMLD012661, and CMLD012693, molecules representing two distinct chemical scaffolds, including 3-hydroxyquinolinones and a xanthone natural product. Based on structural insights, CMLD013360, CMLD012661, and CMLD012693 were hypothesized to exert antifungal activity through metal chelation. Follow-up investigations revealed all three compounds exerted antifungal activity against non-albicans Candida, including Candida auris and Candida glabrata, with the xanthone natural product CMLD013360 also displaying activity against the pathogenic mould Aspergillus fumigatus. Media supplementation with metallonutrients, namely ferric or ferrous iron, rescued C. albicans growth, confirming these compounds act as metal chelators. Thus, this work identifies and characterizes two chemical scaffolds that chelate iron to inhibit the growth of the clinically relevant fungal pathogen C. albicansIMPORTANCEThe worldwide incidence of invasive fungal infections is increasing at an alarming rate. Systemic candidiasis caused by the opportunistic pathogen Candida albicans is the most common cause of life-threatening fungal infection. However, due to the limited number of antifungal drug classes available and the rise of antifungal resistance, an urgent need exists for the identification of novel treatments. By screening a compound collection from the Boston University Center for Molecular Discovery (BU-CMD), we identified three compounds representing two distinct chemical scaffolds that displayed activity against C. albicans. Follow-up analyses confirmed these molecules were also active against other pathogenic fungal species including Candida auris and Aspergillus fumigatus. Finally, we determined that these compounds inhibit the growth of C. albicans in culture through iron chelation. Overall, this observation describes two novel chemical scaffolds with antifungal activity against diverse fungal pathogens.

Clinical experience with intraperitoneal sodium thiosulphate for calciphylaxis in peritoneal dialysis: A case series.

Calciphylaxis is an uncommon but life-threatening syndrome in end-stage kidney disease, characterised by painful medial and intimal calcification of the arterioles in the deep dermis and subcutaneous tissues. Intravenous sodium thiosulfate serves as an off-label but effective treatment in haemodialysis patients. However, this approach confers considerable logistical challenges for affected peritoneal dialysis patients. In this case series, we demonstrate that intraperitoneal administration can be a safe, convenient and long-term alternative.