Exploring cuproptosis as a mechanism and potential intervention target in cardiovascular diseases

Copper (Cu) is a vital trace element for maintaining human health. Current evidence suggests that genes responsible for regulating copper influx and detoxification help preserve its homeostasis. Adequate Cu levels sustain normal cardiac and blood vessel activity by maintaining mitochondrial function. Cuproptosis, unlike other forms of cell death, is characterized by alterations in mitochondrial enzymes. Therapeutics targeting cuproptosis in cardiovascular diseases (CVDs) mainly include copper chelators, inhibitors of copper chaperone proteins, and copper ionophores. In this review, we expound on the primary mechanisms, critical proteins, and signaling pathways involved in cuproptosis, along with its impact on CVDs and the role it plays in different types of cells. Additionally, we explored the influence of key regulatory proteins and signaling pathways associated with cuproptosis on CVDs and determined whether intervening in copper metabolism and cuproptosis can enhance the outcomes of CVDs. The insights from this review provide a fresh perspective on the pathogenesis of CVDs and new targets for intervention in these diseases.

Trastuzumab-conjugated oxine-based ligand for [89Zr]Zr4+ immunoPET

A new, bifunctional chelating ligand for immuno-Positron Emission Tomography (PET) was designed, synthesized, and conjugated to Trastuzumab for a proof-of-concept study with ⁸⁹Zr. H₄neunox was synthesized from the tris(2-aminoethyl)amine backbone, decorated with 8-hydroxyquinoline moieties, and utilizes a primary amine for functionalization. A maleimide moiety extends the chelator to create H₄neunox-mal for antibody conjugation via maleimide-thiol click chemistry. Preliminary ⁸⁹Zr radiolabeling of H₄neunox indicated quantitative radiolabeling at 1 × 10^-5 M, but improved inertness towards human serum (96% intact at 7 d) and Fe³⁺ (92% intact at 24 h) compared to the previously synthesized H₅decaox. The chelator was successfully conjugated to the monoclonal antibody, Trastuzumab, and used in preliminary radiolabeling reactions (37 °C, 2 h) with ⁸⁹Zr. Radiochemical assessments of the new H₄neunox-Trastuzumab conjugate include ⁸⁹Zr radiolabeling, spin filter purification, cell-binding immunoreactivity, and in vivo PET imaging and biodistribution in SKOV-3 tumour bearing nude mice, performed in comparison with the desferrioxamine B analog, DFO-Trastuzumab. The [⁸⁹Zr]Zr(neunox-Trastuzumab) showed lowered inertness towards serum (76% intact at 24 h) as well as demetallation in vivo through bone uptake (21% ID/g) in PET imaging and biodistribution studies when compared to [⁸⁹Zr]Zr(DFO-Trastuzumab). Although the combination of the chelator and antibody had detrimental effects on their intended purposes, nonetheless, the primary amine platform of H₄neunox developed here provides an oxine-based bifunctional ligand for further derivatizations with other targeting vectors.

An On-off Supramolecular Fluorescence Switch for Detection of Pb2+ Ions and Vitamin C

β-cyclodextrin-hydroxyquinoline functionalized graphene oxide (GO-CD-HQ) was facilely fabricated to monitor and quantitatively analyze cations in aqueous media. The optical probe was notably selective enhanced toward Pb²⁺ ions over the other tested ions like Cu²⁺, Hg²⁺, Ca²⁺, Na⁺, K⁺, Zn²⁺, Fe²⁺, Fe³⁺, Ag⁺, Mg²⁺, and Cd²⁺ at 468 nm as an emission wavelength. The probe was shown the best performance in pH value, 5, and optimum time 1 min. Absorption spectra have clearly confirmed the static type fluorescence enhancement mechanism of GO-CD-HQ. Under the optimal conditions, the detection limit of it and linear concentration range for Pb²⁺ ions were obtained as 3.72 × 10^-5 M and (5-60) × 10^-5 M, respectively. Additionally, the developed assay exhibited logic gate behavior with Pb²⁺ ions and vitamin C as a masking agent for cited ions.

Metallocyclodextrins in medicinal chemistry

This review focuses on metal complexes of cyclodextrin (CyD) derivatives designed for application as therapeutics or diagnostics. We discuss examples of metalloprotein models (hemoglobin, superoxide dismutase and catalase) based on cyclodextrins. The hydrophobic microenvironment of CyDs stabilizes the Fe(II) porphyrin system that can reversibly bind O₂ or CO in water. Superoxide dismutase/catalase mimetics exploit functionalization with CyDs, which increase their solubility and biological activity. Furthermore, CyDs have been used as scaffolds to obtain multicenter metal complexes: paramagnetic systems act as high-performance contrast agents for magnetic resonance imaging applications. Finally, we review CyD ligands, whose use appears promising in metal chelation therapy, as CyD moiety confers additional properties to the ligands.

Positional isomers of mannose–quinoline conjugates and their copper complexes: exploring the biological activity

Mannoconjugates show significant antibacterial activity. A regioisomer shows antiproliferative activity with copper(ii) ions.

Cyclodextrins 3-Functionalized with 8-Hydroxyquinolines: Copper-Binding Ability and Inhibition of Synuclein Aggregation

Neurodegenerative diseases such as Parkinson's and Alzheimer's diseases are multifactorial disorders related to protein aggregation, metal dyshomeostasis, and oxidative stress. To advance understanding in this area and to contribute to therapeutic development, many efforts have been directed at devising suitable agents that can target metal ions associated with relevant biomolecules such as α-synuclein. This paper presents a new cyclodextrin-8-hydroxyquinoline conjugate and discusses the properties of four cyclodextrins 3-functionalized with 8-hydroxyquinoline as copper(II) chelators and inhibitors of copper-induced synuclein aggregation. The encouraging results establish the potential of cyclodextrin-8-hydroxyquinoline conjugates as chelators for the control of copper toxicity.

Aminocyclodextrin Oligomers as Protective Agents of Protein Aggregation

Over 30 different amyloid proteins and a number of corresponding protein-misfolding diseases have been identified. Among these is Alzheimer's disease, the most common neurodegenerative disorder. The treatment of these diseases is still a goal to reach and many molecules have been studied in this context. Among these, the cyclodextrins have shown interesting potential as agents against protein aggregation (antiaggregants). On the basis of this interest, we investigated the effect on protein aggregation of some oligomers of β-cyclodextrins. In particular, it was found that amino oligomers show good inhibition of β-amyloid aggregation in the micromolar concentration range. The presence of both a multicavity system and amino groups seems to be essential for preventing protein aggregation.

Cyclodextrins as Protective Agents of Protein Aggregation: An Overview

Cyclodextrins are extensively used in different fields (e.g., catalysis, chromatography, pharma, supramolecular chemistry, bioorganic chemistry, and bioinorganic chemistry), and their applications have been widely reviewed. Their main application in the field of pharmaceutical is as a drug carrier. This review overviews, for the first time, the use of cyclodextrins and their derivatives as antiaggregant agents in a number of proteins (e.g., amyloid-β, insulin, recombinant human growth hormone, prion protein, transthyretin, and α-synuclein) and some multimeric enzymes. There are many diseases that are correlated to protein misfolding and amyloid formation processes affecting numerous organs and tissues. There are over 30 different amyloid proteins and a number of corresponding diseases. Alzheimer's disease is the most common neurodegenerative disease. Treatment of these diseases is still a goal to reach, and many molecules are studied in this perspective. Cyclodextrins have also been studied, and they show great potential; as such, further studies could be very promising. This review aims to be a stimulus for the design of new cyclodextrin derivatives to obtain multifunctional systems with antiaggregant activity.

Trehalose-8-hydroxyquinoline conjugates as antioxidant modulators of Aβ aggregation

The conjugation of trehalose with 8-hydroxyquinoline induces synergistic effects that lead to good antiaggregant ability. The difunctionalization of trehalose produces a better-performing antiaggregant compound.

New Glycoconjugates for the Treatment of Diseases Related to Metal Dyshomeostasis

Metal dyshomeostasis is involved in several pathologies, making metal ions promising therapeutic targets. Conjugating 8-hydroxyquinolines with sugars gave rise to novel derivatives with improved solubility, selectivity, and multifunctionality. Biological evaluation of these compounds suggests they have potential as therapeutic agents in diseases related to metal dyshomeostasis.

Unusual Cyclodextrin Derivatives as a New Avenue to Modulate Self- and Metal-Induced Aβ Aggregation

Mounting evidence suggests an important role of cyclodextrins in providing protection in neurodegenerative disorders. Metal dyshomeostasis is reported to be a pathogenic factor in neurodegeneration because it could be responsible for damage involving oxidative stress and protein aggregation. As such, metal ions represent an effective target. To improve the metal-binding ability of cyclodextrin, we synthesized three new 8-hydroxyquinoline-cyclodextrin conjugates with difunctionalized cyclodextrins. In particular, the 3-difunctionalized regioisomer represents the first example of cyclodextrin with two pendants at the secondary rim, resulting in a promising compound. The derivatives have significant antioxidant capacity and the powerful activity in inhibiting self-induced amyloid-β aggregation seems to be led by synergistic effects of both cyclodextrin and hydroxyquinoline. Moreover, the derivatives are also able to complex metal ions and to inhibit metal-induced protein aggregation. Therefore, these compounds could have potential as therapeutic agents in diseases related to protein aggregation and metal dyshomeostasis.